Description:FIELD
The present disclosure relates to an emulsion and a process for its preparation.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicates otherwise.
Soft monomer refers to a class of monomer that is characterized by a low Tg value and has longer chain alkyl acrylates and exhibit low water solubility (i.e., high hydrophobicity). Examples of soft monomer are n-butyl acrylate, 2-ethyl hexyl acrylate, iso-octyl acrylate and the like.
Hard monomer refers to a class of monomer that is characterized by a high Tg value. Examples of hard monomer are styrene, methyl methacrylate, ethyl acrylate, methyl acrylate and the like.
Functional monomer refers to a class of monomer having various functional groups, such as carboxyl or hydroxyl. Examples of functional monomers are acrylic acid and hydroxyethyl acrylate, which are very water-soluble.
Tint strength refers to the ability of a colorant/pigment to alter the color of a paint film.
Delta E refers to the difference between the displayed color and the original color standard of the input content. Lower Delta E value indicates greater accuracy. High Delta E values indicate a mismatch.
Coverage refers to the area that can be covered by per liter of the paint.
Contrast ratio refers to the ratio of the reflectance of a film when applied on a black substrate to that of an identical film on a white substrate.
Dirt pickup resistance (DPUR) refers to an ability of a coating (e.g. paint) to resist dirt in exposure to natural environments. Though it is named “dirt pickup”, it is not defined in terms of the amount of dirt accumulated on a surface, but in terms of the color change of a surface before and after a period of exposure.
Sheen refers to a visual property of the substance/material that shines with the reflected light.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Emulsion polymers or latex are produced by different processes of polymerization such as seeded emulsion polymerization, semi batch process, core shell process, power-feed methods of polymerization as well as sequential polymerization. Generally, an acrylate monomer such as methyl methacrylate, butyl acrylate, 2-ethyl hexyl acrylate, methacrylic acid, acrylic acid are used as a monomer. The speciality monomers such as t-BA, CHMA, Veova 10 are also used to improve the exterior performance like weatherability. Conventionally, the use of Benzophenone based moieties is known which improves the exterior durability due to the post crosslinking in the presence of sunlight after film formation. However, there is possibility of additive leaching with the use of only ‘Benzophenone’, as it is not bound to the polymer backbone.
Conventionally known processes for emulsion polymerization results in the emulsion polymer having poor dirt pick up resistance, poor elongation, unsatisfactory water resistance and low exterior durability performance. Further, the conventional emulsion polymerization processes are based on harmful, toxic substances such as alkyl phenol ethylene oxide (APEO) surfactants, formaldehyde releasing biocides or preservatives and the like.
Therefore, there is felt a need to develop an emulsion that can mitigate the drawbacks mentioned herein above or at least provide a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows.
An object of the present disclosure is to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
Another object of the present disclosure is to provide an emulsion.
Still another object of the present disclosure is to provide an emulsion that is suitable for paint having prolonged exterior durability.
Yet another object of the present disclosure is to provide an emulsion that result in high dirt pickup resistance (DPUR) along with elongation.
Still another object of the present disclosure is to provide an emulsion that gives prolonged UV crosslinking and UV resistance.
Still another object of the present disclosure is to provide a simple and an environment friendly process for the preparation of an emulsion.
Yet another object of the present disclosure is to provide a coating composition comprising an emulsion.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to an emulsion. The emulsion is a reaction product of monomers selected from a hard monomer, a soft monomer, a speciality monomer, and a functional monomer; an initiator; a surfactant; an additive; and water.
In an embodiment of the present disclosure, the emulsion composition comprises:
a) 10 mass% to 30 mass% of the hard monomer;
b) 10 mass% to 20 mass % of the soft monomer;
c) 0.2 mass% to 10 mass% of the speciality monomer;
d) 0.5 mass% to 5 mass% of the functional monomer;
e) 0.1 mass% to 1 mass% of the initiator;
f) 1 mass% to 5 mass% of the surfactant;
g) 0.1 mass% to 5 mass% of the additive; and
h) q.s. water,
wherein the mass% of each component is with respect to the total mass of the emulsion composition.
In an embodiment of the present disclosure, the hard monomer is selected from the group consisting of methyl methacrylate, styrene, cyclohexyl methacrylate (CHMA), and tert-butyl acrylate (TBA).
In an embodiment of the present disclosure, the soft monomer is selected from the group consisting of butyl acrylate, ethyl hexyl acrylate, vinyl neodecanoate , and ethyl acrylate.
In an embodiment of the present disclosure, the speciality monomer is selected from the group consisting of vinyl neodecanoate, benzophenone methacrylate mixture, and silane monomer.
In an embodiment of the present disclosure, the functional monomer is selected from the group consisting of methacrylic acid (carboxy functional monomer), hydroxyl ethyl methacrylate (HEMA) (hydroxyl functional monomer), dimethyl amino ethyl methacrylate (Visiomer6976) (Functional Monomer -UV Crosslinking) and silane functional monomer (Silane A-171).
In an embodiment of the present disclosure, the initiator is selected from the group consisting of a potassium persulfate, ammonium per sulfate, and sodium persulfate, a first redox initiator and a second redox initiator.
In an embodiment of the present disclosure, the first redox initiator and the second redox initiator are independently selected from the group consisting of tert-butyl hydroperoxide, sodium formaldehydesulfoxylate, tert-butyl hydroperoxide, sodium formaldehydesulfoxylate/Fe (III), ammonium persulfate, sodium bisulfite, sodium hydrosulfite/ Fe(III).
In an embodiment of the present disclosure, the surfactant is selected from the group consisting of an anionic surfactant and non-ionic surfactant.
In an embodiment of the present disclosure, the anionic surfactant is selected from the group consisting of alpha olefin sulfonate, sodium lauryl ethers, alkyl diphenyloxide disulfonate, disodium ethoxylated alcohol half ester of succinic acid, and Alkyl aryl sulfonates.
In an embodiment of the present disclosure, the non-ionic surfactant is selected from the group consisting of fatty alcohol ethoxylate, trididecyl alcohol ethoxylate, linear C9-C11 alcohol ethoxylate, and synthetic C12-C15 alcohol ethoxylate.
In an embodiment of the present disclosure, the additive is selected from the group consisting of a buffer, a preservative, coalescing agent, a defoaming agent, and a neutralizing agent.
In an embodiment of the present disclosure, the buffer is selected from the group consisting of sodium bicarbonate, sodium acetate, and sodium carbonate.
In an embodiment of the present disclosure, the preservative is selected from the group consisting of 5-Chloro-2-methyl-4-isothiazolinone-3-one and 2-Methyl-4-isothiazolinone-3-one CIT/CMIT (Sanitized CI15), and 1,2-Benzisothiazol-3(2H)-one (BIT) (Sanitized BT 10 A).
In an embodiment of the present disclosure, the neutralizing agent is selected from the group consisting of liquid ammonia, sodium hydroxide, and a mixture of organic amine ( pHlex 110).
In an embodiment of the present disclosure, the coalescing agent is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (optifilm enhancer 300), and 3- hydroxy-2,2,4- trimethyl pentyl Isobutyrate (Ruanta C12).
In an embodiment of the present disclosure, the defoaming agent is selected from the group consist of tegofoamex k3 and mineral oil based defoamer.
In an embodiment of the present disclosure, the emulsion as claimed in is characterized by having
• a nonvolatile matter in the range of 45 % to 55%;
• viscosity in the range of 200 cps to 900 cps; and
• minimum film forming temperature in the range of 10 °C to 15 °C.
In another aspect, the present disclosure relates to a process for the preparation of an emulsion. The process comprising the following steps:
i) charging first portions of water, surfactants and a predetermined amount of a buffer in a reactor under stirring followed by heating at a temperature in the range of 80 ºC to 90 ºC for a time period in the range of 20 min to 2 hours to obtain a reactor charge mixture;
ii) separately, mixing second portions of water, surfactants and a first portion of monomers at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a first pre-emulsion;
iii) separately, mixing third portions of water, surfactants, a second portion of monomers and a predetermined amount of coalescing agent at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a second pre-emulsion;
iv) adding a first portion of the first pre-emulsion, followed by adding a first portion of a initiator solution to the reactor charge mixture and further adding a second portion of the first pre-emulsion and mixing for a time period in the range of 2 hours to 3 hours by maintaining the temperature of the reactor in the range of 80 ºC to 90 ºC to obtain a first pre-emulsified mixture, wherein a second portion of the initiator solution is added to the first pre-emulsion just before adding the first pre-emulsion to the reactor charge mixture;
v) adding the second pre-emulsion to the first pre-emulsified mixture by maintaining the temperature of the reactor in the range of 80 ºC to 90 ºC at a time period in the range of 1 hour to 2 hours to obtain a second pre-emulsified mixture; wherein a third portion of the initiator solution is added to the second pre-emulsion just before adding the second pre-emulsion to the first pre-emulsified mixture;
vi) maintaining the second pre-emulsified mixture at the temperature of the reactor in the range of 80 ºC to 90 ºC for a time period in the range of 10 minutes to 20 minutes followed by cooling to a temperature in the range of 70 °C to 78 °C to obtain an intermediate mixture;
vii) adding a predetermined amount of a first redox initiator solution in the intermediate mixture by maintaining the reactor at the temperature in the range of 70 °C to 78 °C for a time period in the range of 5 minutes to 15 minutes followed by adding a predetermined amount of a second redox initiator solution for a time period in the range of 5 minutes to 15 minutes to obtain a first resultant mixture;
viii) maintaining the resultant mixture at a temperature in the range of 70 °C to 78 °C for a time period in the range of 40 minutes to 60 minutes followed by cooling to a temperature of 40 °C to 50 °C to obtain a second resultant mixture; and
ix) adding a predetermined amount of additives to the second resultant mixture for a time period in the range of 25 minutes to 50 minutes to obtain the emulsion.
In an embodiment of the present disclosure, the first portion of the water is in the range of 10 mass% to 20 mass% with respect to the mass% of the emulsion.
In an embodiment of the present disclosure, the first portion of the surfactant is in the range of 0.4 mass% to 1 mass% with respect to the mass% of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of buffer is in the range of 0.05 mass% to 0.3 mass% with respect to the mass% of the emulsion.
In an embodiment of the present disclosure, the second portion of the water is in the range of 10 mass% to 20 mass% with respect to the mass% of the emulsion.
In an embodiment of the present disclosure, the second portion of the surfactants is in the range of 0.4 mass% to 1.5 mass% with respect to the mass% of the emulsion.
In an embodiment of the present disclosure, the first portion of the monomers is in the range of 20 mass% to 30 mass% with respect to the mass% of the emulsion.
In an embodiment of the present disclosure, the first portion of the monomers and the second portion of the monomers are independently selected from the group consisting of a hard monomer, a soft monomer, a speciality monomer, and a functional monomer.
In an embodiment of the present disclosure, the functional monomers are added in the first pre-emulsion and the second pre-emulsion after a time period in the range of 45 minutes to 85 minutes.
In an embodiment of the present disclosure, the first pre-emulsion is added at a rate of 10 g/min to 20/g/min and the second pre-emulsion is added at rate of 15 g/min to 25/g/min.
In an embodiment of the present disclosure, the first portion of the initiator solution is in the range of 2 mass% to 3 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the second portion of the initiator solution is in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the third portion of the initiator solution is in the range of 0.1 mass% to 1 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the first portion of the first pre-emulsion is in the range of 5 mass% to 10 mass% with respect to total mass of the first pre-emulsion and the second portion of the first pre-emulsion is in the range of 90 mass% to 95 mass% with respect to total mass of the first pre-emulsion.
In an embodiment of the present disclosure, the third portion of water is in the range of 5 mass% to 10 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the third portion of surfactants is in the range of 0.5 mass% to 1.5 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the second portion of monomer is in the range of 20 mass% to 25 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of coalescing agent is in the range of 0.1 mass% to 1 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the third portion of the initiator is in the range of 0.01 mass% to 0.1 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of the first redox initiator solution is in the range of 0.5 mass% to 1 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of the second redox initiator solution is in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of additive is in the range of 0.1 mass% to 5 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, each additive is separately mixed in a predetermined amount of water followed by stirring for time period in the range of 5 minutes to 15 minutes, and wherein the predetermined amount of water is in the range of 2.5 mass% to 3.5 mass% with respect to the total mass of the emulsion.
Still in another aspect, the present disclosure relates to a coating composition. The coating composition comprises the emulsion in an amount in the range of 10 mass% to 60 mass%, a pigment in an amount in the range of 5 mass% to 30 mass%, an extender in an amount in the range of 1 mass% to 10 mass%, additives in an amount in the range of 0.5 mass % to 10 mass%, wherein the mass% are with respect to the total mass of the coating composition.
In an embodiment of the present disclosure, the pigment is selected from the group consisting of titanium dioxide, anatase and rutile.
In an embodiment of the present disclosure, the extender is selected from the group consisting of talc and calcium carbonate.
In an embodiment of the present disclosure, the additive is selected from the group consisting of fluro based additives, silane based additives, and preservatives.
In an embodiment of the present disclosure, the coating composition is characterized by having a viscosity in the range of 15000 cps to 19000 cps and pigment volume concentration in the range of 30 mass% to 35 mass%.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates (a) tint strength of the standard coating composition, and (b) tint strength of the coating composition prepared in accordance with the present disclosure (experiment 1);
Figure 2 illustrates DPUR results of the (a) standard coating composition, (b) coating composition prepared in accordance with the present disclosure (experiment 1); and
Figure 3 illustrates QUV results after 1500 hours (a) of the standard coating composition, (b) coating composition prepared in accordance with the present disclosure (experiment 1) and (c) coating composition prepared in accordance with the present disclosure (repeat experiment).
DETAILED DESCRIPTION
The present disclosure relates to an emulsion and a process for its preparation.
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Emulsion polymers or latex are produced by different processes of polymerization such as seeded emulsion polymerization, semi batch process, core shell process, power-feed methods of polymerization as well as sequential polymerization. Generally, an acrylate monomer is used such as methyl methacrylate, butyl acrylate, 2-ethyl hexyl acrylate, methacrylic acid, acrylic acid as monomers. The speciality monomers such as t-BA, CHMA, Veova 10 are also used to improve the exterior performance like weatherability. Conventionally, the use of Benzophenone based moieties is known which improves the exterior durability due to the post crosslinking in the presence of sunlight after film formation. However, there is possibility of additive leaching with the use of only ‘Benzophenone’, as it is not bound to the polymer backbone.
Conventionally known processes for emulsion polymerization results in the emulsion polymer having poor dirt pick up resistance, poor elongation, unsatisfactory water resistance and low exterior durability performance. Further, the conventional emulsion polymerization processes are based on harmful, toxic substances such as alkyl phenol ethylene oxide (APEO) surfactants, formaldehyde releasing biocides or preservatives and the like.
The present disclosure provides an emulsion and a process for its preparation.
In an aspect, the present disclosure provides an emulsion.
The emulsion is a reaction product of:
a. monomers selected from a hard monomer, a soft monomer, a speciality monomer, and a functional monomer;
b. an initiator;
c. a surfactant;
d. an additive; and
e. water.
In an embodiment of the present disclosure, the emulsion comprises
a) 10 mass% to 30 mass% of the hard monomer;
b) 10 mass% to 20 mass % of the soft monomer;
c) 0.2 mass% to 10 mass% of the speciality monomer;
d) 0.5 mass% to 5 mass% of the functional monomer;
e) 0.1 mass% to 1 mass% of the initiator;
f) 1 mass% to 5 mass% of the surfactant;
g) 0.01 mass% to 5 mass% of the additive; and
h) q.s. water,
wherein the mass% of each component is with respect to the total mass of the emulsion.
In an exemplary embodiment of the present disclosure, the emulsion comprises:
a) 19.5 mass% of the hard monomer;
b) 18.5 mass % of the soft monomer;
c) 8 mass% of the speciality monomer;
d) 3.2 mass% of the functional monomer;
e) 0.28 mass% of the initiator;
f) 2.2 mass% of the surfactant;
g) 1.6 mass% of the additive; and
h) q.s. water,
wherein the mass% of each component is with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the hard monomer is selected from the group consisting of methyl methacrylate, styrene, cyclohexyl methacrylate (CHMA), and tert-butyl acrylate (TBA). In an exemplary embodiment of the present disclosure, the hard monomer is methyl methacrylate.
In an embodiment of the present disclosure, the soft monomer is selected from the group consisting of butyl acrylate ethyl hexyl acrylate, vinyl neodecanoate, and ethyl acrylate. In an exemplary embodiment of the present disclosure, the soft monomer is butyl acrylate.
In an embodiment of the present disclosure, the speciality monomer is selected from the group consisting of vinyl neodecanoate, benzophenone methacrylate mixture, and silane monomer. In an exemplary embodiment of the present disclosure, the speciality monomer is vinyl neodecanoate.
Benzophenone and its derivative are well known to the performance improvement of exterior architectural paints. This additive (Benzophenone) improves the performance to certain extent only and as it is not bound to the polymer backbone, it may leave out over a period. To take the performance to next level, the inventors of the present disclosure have used a polymerizable benzophenone moiety (Benzophenone Methacrylate –Visiomer 6976 from Evonik), which binds to the polymer and give prolonged UV crosslinking and UV Resistance. This performs well as it is bound to the polymer backbone and maintains good durability.
In an embodiment of the present disclosure, the functional monomer is selected from the group consisting of methacrylic acid, vinyltrimethoxy silane, dimethyl amino ethyl methacrylate and hydroxyl ethyl methacrylate. In an exemplary embodiment of the present disclosure, the functional monomer is methacrylic acid. In another exemplary embodiment of the present disclosure, the functional monomer is vinyltrimethoxy silane. Still, in another exemplary embodiment of the present disclosure, the functional monomer is hydroxyl ethyl methacrylate. Yet, in another exemplary embodiment of the present disclosure, the functional monomer is dimethyl amino ethyl methacrylate.
Addition of hydroxyl functional monomer like hydroxyl ethyl methacrylate improves the Dirt Pick Up Resistance of resulting paint film, so this monomer is also included in the monomer backbone in the sequential emulsion polymerization.
In an embodiment of the present disclosure, the initiator is selected from the group consisting of potassium persulfate, ammonium per sulfate, and sodium persulfate., a first redox initiator and a second redox initiator.
. In an exemplary embodiment of the present disclosure, the initiator is potassium persulfate (PPS).
In an embodiment of the present disclosure, the first redox initiator and the second redox initiator are independently selected from the group consisting of tert-butyl hydroperoxide, sodium formaldehydesulfoxylate, tert-butyl hydroperoxide, sodium formaldehydesulfoxylate/Fe (III), ammonium persulfate, sodium bisulfite, sodium hydrosulfite/ Fe(III). In an exemplary embodiment of the present disclosure, the first redox initiator is tert-butyl hydroperoxide. In an exemplary embodiment of the present disclosure, the second redox initiator is sodium formaldehydesulfoxylate.
In an embodiment of the present disclosure, the surfactant is selected from the group consisting of an anionic surfactant and a non-ionic surfactant.
In an embodiment of the present disclosure, the anionic surfactant is selected from the group consisting of alpha olefin sulfonate, sodium lauryl ethers, alkyl diphenyloxide disulfonate, disodium ethoxylated alcohol half ester of succinic acid, and alkyl aryl sulfonates; and the non-ionic surfactant is selected from the group consisting of fatty alcohol ethoxylate, trididecyl alcohol ethoxylate, linear C9-C11 alcohol ethoxylate, and synthetic C12-C15 alcohol ethoxylate.
In an exemplary an embodiment of the present disclosure, the anionic surfactant is alpha olefin sulfonate, and the non-ionic surfactant is fatty alcohol ethoxylate.
In an embodiment of the present disclosure, the additive is selected from the group consisting of a buffer, coalescing agent, a preservative, a defoaming agent, and a neutralizing agent.
In an embodiment of the present disclosure, the buffer is selected from the group consisting of sodium bicarbonate, sodium acetate, sodium carbonate. In an exemplary embodiment of the present disclosure, the buffer is sodium bicarbonate.
In an embodiment of the present disclosure, the preservative is selected from the group consisting of CIT/CMIT (Sanitized CI15), and BIT (Sanitized BT 10 A). In an exemplary embodiment of the present disclosure, the preservative is selected CIT/CMIT (Sanitized CI15). In an exemplary embodiment of the present disclosure, the preservative is BIT (Sanitized BT 10 A).
In an embodiment of the present disclosure, the neutralizing agent is selected from the group consisting of liquid ammonia, sodium hydroxide, and mixture of organic amine (Phlex 110). In an exemplary embodiment of the present disclosure, the neutralizing agent is liquid ammonia.
In an embodiment of the present disclosure, the coalescing agent is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, and 3- hydroxy-2,2,4- trimethyl pentyl isobutyrate (Ruanta C12). In an exemplary embodiment of the present disclosure, the coalescing agent 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.
In an embodiment of the present disclosure, the defoaming agent is selected from the group consisting of tegofoamex k3, (mineral oil based defoamer). In an exemplary embodiment of the present disclosure, the defoaming agent is tegofoamex k3.
The surfactants used in the emulsion of the present disclosure are environment friendly i.e., alkyl phenol ethylene oxide (APEO) free. Further, the preservatives used in the emulsion of the present disclosure do not release any formaldehyde.
Thus, the present disclosure provides an environment friendly emulsion which improves the exterior weatherability. The UV crosslinking monomers improve the hardness and crosslink in sunlight. The weatherability and durability are measured by balanced performance of dirt pick up resistance and elasticity.
In an embodiment of the present disclosure, the emulsion is characterized by having:
• a nonvolatile matter in the range of 45 % to 55%;
• viscosity in the range of 200 cps to 900 cps; and
• minimum film forming temperature in the range of 10 °C to 15 °C
In an exemplary embodiment of the present disclosure, the emulsion is characterized by having:
• a nonvolatile matter of 50%;
• viscosity of 500 cps
• minimum film forming temperature of 12 °C.
In another aspect, the present disclosure provides a process for the preparation of an emulsion. The process comprises the following steps
i) charging first portions of water, surfactants and a predetermined amount of a buffer in a reactor under stirring followed by heating at a temperature in the range of 80 ºC to 90 ºC for a time period in the range of 20 minutes to 2 hours to obtain a reactor charge mixture;
ii) separately, mixing second portions of water, surfactants and a first portion of monomers at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a first pre-emulsion;
iii) separately, mixing third portions of water, surfactants, a second portion of monomers and a predetermined amount of coalescing agent at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a second pre-emulsion;
iv) adding a first portion of the first pre-emulsion, followed by adding a first portion of a initiator solution to the reactor charge mixture and further adding a second portion of the first pre-emulsion and mixing for a time period in the range of 2 hours to 3 hours by maintaining the temperature of the reactor in the range of 80 ºC to 90 ºC to obtain a first pre-emulsified mixture, wherein a second portion of the initiator solution is added to the first pre-emulsion just before adding the first pre-emulsion to the reactor charge mixture;
v) adding the second pre-emulsion to the first pre-emulsified mixture by maintaining the temperature of the reactor in the range of 80 ºC to 90 ºC at a time period in the range of 1 hour to 2 hours to obtain a second pre-emulsified mixture; wherein a third portion of the initiator solution is added to the second pre-emulsion just before adding the second pre-emulsion to the first pre-emulsified mixture;
vi) maintaining the second pre-emulsified mixture at the temperature of the reactor in the range of 80 ºC to 90 ºC for a time period in the range of 10 minutes to 20 minutes followed by cooling to a temperature in the range of 70 °C to 78 °C to obtain an intermediate mixture;
vii) adding a predetermined amount of a first redox initiator solution in the intermediate mixture by maintain the reactor at the temperature in the range of 70 °C to 78 °C for a time period in the range of 5 minutes to 15 minutes followed by adding a predetermined amount of a second redox initiator solution for a time period in the range of 5 minutes to 15 minutes to obtain a first resultant mixture;
viii) maintaining the resultant mixture at a temperature in the range of 70 °C to 78 °C for a time period in the range of 40 minutes to 60 minutes followed by cooling to a temperature of 40 °C to 50 °C to obtain a second resultant mixture; and
ix) adding a predetermined amount of additives in the second resultant mixture under stirring for a time period in the range of 20 minutes to 3 hours to obtain the emulsion.
The process is described in detail.
In a first step, first portions of water, surfactants and a predetermined amount of a buffer are charged in a reactor under stirring followed by heating at a temperature in the range of 80 ºC to 90 ºC for a time period in the range of 20 minutes to 2 hours to obtain a reactor charge mixture.
In an exemplary embodiment of the present disclosure, the temperature is 83 °C to 85 °C.
In an exemplary embodiment of the present disclosure, the time period is 50 minutes.
In an embodiment of the present disclosure, the first portion of the water is in the range of 10 mass% to 20 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the water is 15.5 mass% with respect to the mass % of the emulsion.
In an exemplary embodiment the water is demineralized water.
In an embodiment of the present disclosure, the first portion of the surfactant is in the range of 0.4 mass% to 1 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the surfactant is 0.5 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the first portion of the surfactant comprises anionic surfactant in an amount in the range of 0.2 mass% to 0.5 mass% and; nonionic surfactant in an amount in the range of 0.1 mass% to 0.3 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the surfactant comprises anionic surfactant in an amount of 0.3 mass% and nonionic surfactant in an amount of 0.2 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the first portions of surfactants are selected from the group consisting of an anionic surfactant and non-ionic surfactant. In an exemplary embodiment of the present disclosure, the first portion of surfactants is a mixture of anionic surfactant and non-ionic surfactant.
In an embodiment of the present disclosure, the anionic surfactant is selected from the group consisting of alpha olefin sulfonate (Kemsurf OS38), sodium lauryl ethers, alkyl diphenyloxide disulfonate, disodium ethoxylated alcohol half ester of succinic acid, alkyl aryl sulfonates. In an exemplary embodiment of the present disclosure, the anionic surfactant is alpha olefin sulfonate (Kemsurf OS38).
In an embodiment of the present disclosure, the non-ionic surfactant is selected from the group consisting of fatty alcohol ethoxylate, trididecyl alcohol ethoxylate, linear C9-C11 alcohol ethoxylate, and synthetic C12-C15 alcohol ethoxylate (ATSURF140/70G). In an exemplary embodiment of the present disclosure, the non-ionic surfactant is fatty alcohol ethoxylate.
In an embodiment of the present disclosure, the predetermined amount of the buffer solution is in the range of 2 mass% to 3 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the predetermined amount of the buffer solution is 2.6 mass% with respect to the total mass of the emulsion.
In an exemplary embodiment of the present disclosure, the buffer solution comprises demineralized water in an amount of 2.5 mass % and buffer in an amount of 0.17 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of buffer is in the range of 0.05 mass% to 0.3 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the buffer is 0.17 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the buffer is selected from the group consisting of sodium bicarbonate, sodium acetate, and sodium carbonate. In an exemplary embodiment of the present disclosure, the buffer is sodium bicarbonate.
In a second step, separately, second portions of water, surfactants and a first portion of monomers are mixed at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a first pre-emulsion.
In an exemplary embodiment of the present disclosure, the temperature is 30 ºC (room temperature).
In an exemplary embodiment of the present disclosure the time period is 1 hour 30 minutes.
In an embodiment of the present disclosure, the second portion of the water is in the range of 10 mass% to 20 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the second portion of the water is 13.3 mass% with respect to the total mass % of the emulsion.
In an embodiment of the present disclosure, the second portion of the surfactants is in the range of 0.4 mass% to 1.5 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the second portion of the surfactants is 0.8 mass% with respect to the total mass % of the emulsion.
In an embodiment of the present disclosure, the first portion of the monomers is in the range of 20 mass% to 30 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the monomers is 26.8 mass% with respect to the total mass % of the emulsion.
In an embodiment of the present disclosure, the first portion of the monomer comprises hard monomer in an amount in the range of 10 mass % to 15 mass% of with respect to the total mass of the emulsion, soft monomer in an amount in the range of 10 mass% to 15 mass% with respect to the total mass of the emulsion and functional monomer in an amount in the range of 0.4 mass% to 1 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the monomer comprises hard monomer in an amount of 14 mass% of with respect to the total mass of the emulsion, soft monomer in an amount of 12 mass% with respect to the total mass of the emulsion and functional monomer in an amount of 0.5 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the first portion of the monomers is selected from the group consisting of a hard monomer, a soft monomer, a speciality monomer, and a functional monomer.
In an embodiment of the present disclosure, the hard monomer is selected from the group consisting of methyl methacrylate, styrene, cyclohexyl methacrylate (CHMA), and tert-butyl acrylate (TBA). In an exemplary embodiment of the present disclosure, the hard monomer is methyl methacrylate.
In an embodiment of the present disclosure, the soft monomer is selected from the group consisting of butyl acrylate, ethyl hexyl acrylate, vinyl neodecanoate, and ethyl acrylate. In an exemplary embodiment of the present disclosure, the soft monomer is butyl acrylate.
In an embodiment of the present disclosure, the functional monomer is selected from the group consisting of methacrylic acid, vinyltrimethoxy silane, hydroxyl ethyl methacrylate, and dimethyl amino ethyl methacrylate. In an exemplary embodiment of the present disclosure, the functional monomer is methacrylic acid. . In another exemplary embodiment of the present disclosure, the functional monomer is vinyltrimethoxy silane (Silane A-171).
In an embodiment of the present disclosure, the at least one functional monomers are added in the first pre-emulsion and the second pre-emulsion after a time period in the range of 45 minutes to 85 minutes.
In an exemplary embodiment of the present disclosure, the at least one functional monomer is added in the first pre-emulsion after a time period of 60 minutes.
In a third step, separately, third portions of water, surfactants, a second portion of monomers and a predetermined amount of coalescing agent are mixed at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a second pre-emulsion.
In an exemplary embodiment of the present disclosure, the temperature is 30 ºC (room temperature).
In an exemplary embodiment of the present disclosure the time period is 1 hours 15 minutes.
In an embodiment of the present disclosure, the third portion of water is in the range of 5 mass% to 10 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the third portion of water is 6.5 mass% with respect to the mass % of the emulsion.
In an exemplary embodiment of the present disclosure, the water is distilled water.
In an embodiment of the present disclosure, third portion of surfactants is in the range of 0.5 mass% to 1.5 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, the third portion of surfactants is 0.8 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the third portion of the surfactant comprises an anionic surfactant in an amount in the range of 0.3 mass% to 0.5 mass% and; nonionic surfactant in an amount in the range of 0.3 mass% to 0.5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the third portion of the surfactant comprises anionic surfactant in an amount of 0.4 mass% and; nonionic surfactant in an amount of 0.4 mass% with respect to the total mass of the emulsion.
In an exemplary embodiment of the present disclosure, the third portion of the surfactant comprises alpha olefin sulfonate (anionic surfactant) in an amount of 0.4 mass% and fatty alcohol ethoxylate (nonionic surfactant) in an amount of 0.4 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the third portions of surfactants are selected from the group consisting of an anionic surfactant and non-ionic surfactant. In an exemplary embodiment of the present disclosure, the third portion of surfactants is a mixture of anionic surfactant and non-ionic surfactant.
In an embodiment of the present disclosure, the anionic surfactant is selected from the group consisting of alpha olefin sulfonate (Kemsurf OS38), sodium lauryl ethers, alkyl diphenyloxide disulfonate, disodium ethoxylated alcohol half ester of succinic acid, alkyl aryl sulfonates. In an exemplary embodiment of the present disclosure, the anionic surfactant is alpha olefin sulfonate (Kemsurf OS38).
In an embodiment of the present disclosure, the non-ionic surfactant is selected from the group consisting of fatty alcohol ethoxylate, trididecyl alcohol ethoxylate, linear C9-C11 alcohol ethoxylate, and synthetic C12-C15 alcohol ethoxylate (ATSURF140/70G). In an exemplary embodiment of the present disclosure, the non-ionic surfactant is fatty alcohol ethoxylate.
In an embodiment of the present disclosure, second portion of monomer is in the range of 20 mass% to 25 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, second portion of monomer is 22.3 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the second portion of monomer comprises hard monomer in an amount in the range of 5 mass% to 6 mass%, soft monomer in an amount in the range of 6 mass% to 7 mass%, speciality monomer in an amount in the range of 6 mass% to 10 mass%, and functional monomer in an amount in the range of 2 mass% to 2.5 mass%, wherein the mass% is with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the second portion of monomer comprises hard monomer in an amount of 5.5 mass%, soft monomer in an amount of 6.5 mass%, speciality monomer in an amount of 8 mass%, and functional monomer in an amount of 2.3 mass%, wherein the mass% is with respect to the total mass of the emulsion.
In an exemplary embodiment of the present disclosure, the second portion of monomer comprises methyl metha acrylate (hard monomer) in an amount of 5.5 mass%, butyl acrylate (soft monomer) in an amount of 6.5 mass%, vinyl neodecanoate (speciality monomer) in an amount of 8 mass%, (Hydroxyethyl)methacrylate (HEMA) (functional monomer) in an amount of 1.5 mass%, wherein the mass% is with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the second portion of the monomers is selected from the group consisting of a hard monomer, a soft monomer, a speciality monomer, and a functional monomer.
In an embodiment of the present disclosure, the hard monomer is selected from the group consisting of methyl methacrylate, styrene, cyclohexyl methacrylate (CHMA), and tert-butyl acrylate (TBA). In an exemplary embodiment of the present disclosure, the hard monomer is methyl methacrylate.
In an embodiment of the present disclosure, the soft monomer is selected from the group consisting of butyl acrylate, ethyl hexyl acrylate, vinyl neodecanoate (VEOVA10), and ethyl acrylate. In an exemplary embodiment of the present disclosure, the soft monomer is vinyl neodecanoate (VEOVA10).
In an embodiment of the present disclosure, the functional monomer is selected from the group consisting of methacrylic acid (MMA), vinyltrimethoxy silane, hydroxyl ethyl methacrylate (HEMA), and dimethyl amino ethyl methacrylate (Visiomer 6976). In an exemplary embodiment of the present disclosure, the functional monomer is a mixture of methacrylic acid, hydroxyl ethyl methacrylate (HEMA) and dimethyl amino ethyl methacrylate (Visiomer 6976).
Functional monomer Visiomer 6976, a mixture of Methacrylic acid, Methyl methacrylate, Benzophenone methacrylate is added in second pre-emulsion such that particle size will be controlled and exterior wetherability of the paint is improved. Exterior Wetherability is indicated by QUV results.
Functional monomer hydroxyethyl methacrylate (HEMA) is added in the second pre-emulsion. This monomer improves the DUPR of the final coating composition. Also it improves QUV performance by supporting activity of Benzophenone Methacrylate from dimethylamino ethyl methacrylate.
Vinyl neodecanoate (Soft Speciality Monomer) have excellent wetherablity. It is added in the second pre-emulsion specifically so that it will remain on the outer part of the polymer and resulting particle. After subsequent film formation will improve the DPUR.
The functional monomer, methacrylic acid (MAA) is distributed in two pre-emulsions such that particle size will be controlled and adhesion is maintained.
In an embodiment of the present disclosure, predetermined amount of coalescing agent is in the range of 0.1 mass% to 1 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, predetermined amount of coalescing agent is 0.5 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the coalescing agent is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (optifilm enhancer 300), and 3- hydroxy-2,2,4- trimethyl pentyl Isobutyrate (Ruanta C12). In an exemplary embodiment of the present disclosure, the coalescing agent 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.
Optifilm Enhancer 300 helps in the film formation of emulsion and subsequent coating film. It also helps in better elongation of the film.
In an embodiment of the present disclosure, third portion of the initiator is in the range of 0.01 mass% to 0.1 mass% with respect to the mass % of the emulsion. In an exemplary embodiment of the present disclosure, third portion of the initiator 0.05 mass% with respect to the mass % of the emulsion.
In an embodiment of the present disclosure, the initiator is selected from the group consisting of potassium persulfate, ammonium per sulfate, and sodium persulfate. In an exemplary embodiment of the present disclosure, the initiator is potassium persulfate
In an exemplary embodiment of the present disclosure, the at least one functional monomers is added in the second pre-emulsion after a time period of 60 minutes.
In an embodiment of the present disclosure, the functional monomer is selected from the group consisting of methacrylic acid, vinyltrimethoxy silane, hydroxyl ethyl methacrylate, and dimethyl amino ethyl methacrylate (Visiomer 6976). In an exemplary embodiment of the present disclosure, the functional monomer is vinyltrimethoxy silane (Silane A-171).
In a fourth step, a first portion of the first pre-emulsion is added in the reactor charge mixture followed by adding a first portion of a first initiator solution and further adding a second portion of the first pre-emulsion and mixing for a time period in the range of 2 hours to 3 hours by maintaining the temperature of the reactor in the range 80 ºC to 90 ºC to obtain a first pre-emulsified mixture, wherein a second portion of the initiator solution is added to the first pre-emulsion just before adding the first pre-emulsion to the reactor charge mixture;
In an exemplary embodiment of the present disclosure, the temperature is maintained at 83 °C to 85 °C.
In an exemplary embodiment of the present disclosure, the time period is 2.5 hours.
In an embodiment of the present disclosure, the first portion of the first pre-emulsion is in the range of 5 mass% to 10 mass% with respect to total mass of the first pre-emulsion. In an exemplary embodiment of the present disclosure, the first portion of the first pre-emulsion is 8 mass% with respect to total mass of the first pre-emulsion.

In an embodiment of the present disclosure, the second portion of the first pre-emulsion is in the range of 90 mass% to 95 mass% with respect to total mass of the first pre-emulsion. In an exemplary embodiment of the present disclosure, the second portion of the first pre-emulsion is 92 mass% with respect to total mass of the first pre-emulsion.
In an embodiment of the present disclosure, the first pre-emulsion is added at a rate of 10 g/min to 20/g/min. In an exemplary embodiment of the present disclosure, the first pre-emulsion is added at a rate of 16.28 /g/min.
In an embodiment of the present disclosure the initiator is selected from the group consisting of potassium persulfate, ammonium per sulfate, and sodium persulfate. In an exemplary embodiment of the present disclosure the initiator is potassium persulfate.
In an embodiment of the present disclosure, the first portion of the initiator solution is in the range of 2 mass% to 3 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the first portion of the initiator solution is 2.6 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the first portion of the initiator solution comprises the initiator in an amount in the range of 0.1 mass% to 0.2 mass% with respect to the total mass of the emulsion and water in an amount in the range of 2 to 3 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the initiator solution comprises the initiator in an amount of 0.13 mass% with respect to the total mass of the emulsion and water in an amount of 2.5 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the second portion of the initiator solution is in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the second portion of the initiator solution is 0.9 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the second portion of the initiator solution comprises initiator in an amount in the range of 0.08 mass% to 0.2 mass% with respect to the total mass of the emulsion and water in an amount in the range of 0.1 to 1 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the initiator solution comprises the initiator in an amount of 0.1 mass% with respect to the total mass of the emulsion and water in an amount of 0.8 mass% with respect to the total mass of the emulsion.
In a fifth step, the second pre-emulsion is added to the first pre-emulsified mixture by maintaining the temperature of the reactor in the range of 80 ºC to 90 ºC at a time period in the range of 1 hour to 2 hours to obtain a second pre-emulsified mixture, wherein a third portion of the initiator solution is added to the second pre-emulsion just before adding the second pre-emulsion to the first pre-emulsified mixture.
In an exemplary embodiment of the present disclosure, the temperature is maintained at 83 °C to 85 °C.
In an exemplary embodiment of the present disclosure, the time period is 1.5 hours.
In an embodiment of the present disclosure, the second pre-emulsion is added at rate of 15 g/min to 25/g/min. In an exemplary embodiment of the present disclosure, the second pre-emulsion is added at rate of 20/g/min.
In an embodiment of the present disclosure, the third portion of the initiator solution is in the range of 0.1 mass% to 1 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the third portion of the initiator solution is 0.55 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the third portion of the initiator solution comprises initiator in an amount in the range of 0.01 mass% to 0.08 mass% with respect to the total mass of the emulsion and water in an amount in the range of 0.1 to 1 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the initiator solution comprises the initiator in an amount of 0.05 mass% with respect to the total mass of the emulsion and water in an amount of 0.5 mass% with respect to the total mass of the emulsion.
In a sixth step, the second pre-emulsified mixture is maintained at the temperature of the reactor in the range of 80 ºC to 90 ºC for a time period in the range of 10 minutes to 20 minutes followed by cooling to a temperature in the range of 70 °C to 78 °C to obtain an intermediate mixture.
In an exemplary embodiment of the present disclosure, the temperature is maintained at 83 °C to 85 °C for a time period of 15 minutes followed by cooling to a temperature of 75 ºC.
In a seventh step, a predetermined amount of a first redox initiator solution is added in the intermediate mixture by maintaining the reactor at the temperature in the range of 70 °C to 78 °C for a time period in the range of 5 minutes to 15 minutes followed by adding a predetermined amount of a second redox initiator solution for a time period in the range of 5 minutes to 15 minutes to obtain a first resultant mixture.
In an exemplary embodiment of the present disclosure, the reactor is maintained at a temperature of 75 ºC for a time period of 10 minutes.
In an exemplary embodiment of the present disclosure, the second redox initiator solution is added for a time period of 10 minutes.
In an embodiment of the present disclosure, the predetermined amount of the first redox initiator solution is in the range of 0.5 mass% to 1 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the predetermined amount of the first redox initiator solution is 0.62 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the first redox initiator solution comprises redox initiator in an amount in the range of 0.01 mass% to 0.05 mass % with respect to the total mass of the emulsion, the non-ionic surfactant in an amount in the range of 0.08 mass% to 0.2 mass% with respect to the total mass of the emulsion, and water in an amount in the range of 0.1 mass% to 0.5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the first redox initiator solution comprises redox initiator in an amount of 0.04 mass % with respect to the total mass of the emulsion, the non-ionic surfactant in an amount of 0.1 mass% with respect to the total mass of the emulsion, and water in an amount of 0.48 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the predetermined amount of the second redox initiator solution is in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of the emulsion. In an embodiment of the present disclosure, the predetermined amount of the second redox initiator solution is 1.04 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the second redox initiator solution comprises redox initiator in an amount in the range of 0.01 mass% to 0.05 mass % with respect to the total mass of the emulsion, and water in an amount in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of the emulsion. In an embodiment of the present disclosure, the second redox initiator solution comprises redox initiator in an amount of 0.04 mass % with respect to the total mass of the emulsion, and water in an amount of 1 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the first redox initiator and the second redox initiator are independently selected from the group consisting of tert-butyl hydroperoxide, sodium formaldehydesulfoxylate, tert-butyl hydroperoxide, sodium formaldehydesulfoxylate/Fe (III), ammonium persulfate, sodium bisulfite, sodium hydrosulfite/ Fe(III). In an exemplary embodiment of the present disclosure, the first redox initiator is tert-butyl hydroperoxide (TBHP) and the second redox initiator is sodium formaldehydesulfoxylate (SFS).
In an eighth step, the resultant mixture is maintained at a temperature in the range of 70 °C to 78 °C for a time period in the range of 40 minutes to 60 minutes followed by cooling to a temperature of 40 °C to 50 °C to obtain a second resultant mixture.
In an exemplary embodiment of the present disclosure, the resultant mixture is maintained at a temperature of 75 ºC for 50 minutes followed by cooling to a temperature of 45 ºC.
In a final step, predetermined amount of additives are added in the second resultant mixture under stirring for a time period in the range of 20 minutes to 3 hours to obtain the emulsion.
In an embodiment of the present disclosure, the predetermined amount of additive is in the range of 0.1 mass% to 5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the predetermined amount of additive is in an amount of 1.6 mass% with respect to the total mass of the emulsion.
In an embodiment of the present disclosure, the additive is selected from the group consisting of a preservative, a defoaming agent, and a neutralizing agent.
In an embodiment of the present disclosure, the preservative is selected from the group consisting of CIT/CMIT (Sanitized CI15), and BIT (Sanitized BT 10 A). In an exemplary embodiment of the present disclosure, the preservative is CIT/CMIT. In another exemplary embodiment of the present disclosure, the preservative is BIT.
In an embodiment of the present disclosure, the neutralizing agent is selected from the group consisting of liquid ammonia, sodium hydroxide, and mixture of organic amine ( Phlex 110). In an exemplary embodiment of the present disclosure, the neutralizing agent is liquid ammonia.
In an embodiment of the present disclosure, the defoaming agent is selected from the group consist of tegofoamex k3, and mineral oil based defoamer. In an exemplary embodiment of the present disclosure, the defoaming agent is tegofoamex k3.
In an embodiment of the present disclosure, a predetermined amount of neutralizing agent is added in the second resultant mixture followed by adding a predetermined amount of atleast one preservative under stirring for a time period in the range of 5 minutes to 15 minutes, a predetermined amount of at least one defoaming agent under stirring for a time period in the range of 5 minutes to 15 minutes and water to obtain the emulsion.
In an exemplary embodiment of the present disclosure, 0.75 mass% of neutralizing agent is added in the second resultant mixture followed by adding 0.15 mass% of atleast one preservative under stirring for a time period of 10 min, 0.1 mass% of at least one preservative under stirring for a time period of 10 min, 0.004 mass% of a defoaming agent under stirring for a time period of 10 minutes and water to obtain the emulsion.
In an exemplary embodiment of the present disclosure, the preservative is added in the form of solution comprising 0.15 mass% of preservative and 0.3 mass% of water. In another exemplary embodiment of the present disclosure, the preservative is added in the form of a solution comprising 0.1 mass% of preservative and 0.2 mass% of water, wherein the mass% are with respect to the total mass of the emulsion.

In an embodiment of the present disclosure, the emulsion is characterized by having:
• a non volatile matter in the range of 45 % to 55%;
• viscosity in the range of 200 cps to 900 cps; and
• minimum film forming temperature in the range of 10 °C to 15 °C
In an exemplary embodiment of the present disclosure, the emulsion is characterized by having:
• a non volatile matter of 50%;
• viscosity of 485 cps; and
• minimum film forming temperature of 10 °C.
The glass transition temperature (Tg) of the monomers used in the emulsion is 7.9 °C. The glass transition temperature (Tg) of the monomers used in the first pre-emulsion 12.5 °C. The glass transition temperature (Tg) of the monomers used in the second pre-emulsion 2.58 °C.
Tg is glass transition temperature. It is related to dried emulsion film hardness / tackiness. The tackiness /hardness of the film is related to Dirt Pick Up Resistance and Elongation.
The monomers are adjusted such that 55 mass% of the monomers with respect to total mass of the monomers is used in the first pre-emulsion and 45 mass% of the monomers with respect to total mass of the monomers is used in the second pre-emulsion.
The sequential addition of first pre-emulsion (addition of hydrophobic monomers) improves the hardness and contributes to improved DPUR and QUV performance. The hydrophobic monomer vinyl neodecanoate (Veova 10) is kept in the second pre-emulsion so as to further improve DPUR and QUV performance. And finally UV crosslinking monomer is added in the second pre-emulsion so as to get the further improved performance of DPUR and QUV.
The Inventors of the present disclosure have developed an emulsion polymer through sequential emulsion polymerization using conventional monomers along with the speciality monomer such as Veova 10. The monomer composition and the sequence of addition are adjusted in such a way that the dried film will give balance of Dirt Pick Up Resistance and Elongation.
Soft Speciality Monomer such as Veova 10 has excellent wetherablity. It is added in the pre-emulsion 2 specifically so that it will remain on the outer part of the polymer and resulting particle. After subsequent film formation will improve the DPUR.
This combination and sequence of monomer improves water resistance and exterior durability performance. The durability performance also includes the balance of the Tensile Strength and Elongation.
In accordance with the present disclosure, the emulsion has been developed by using the sequential emulsion polymerization process and the ratio of monomers are adjusted to get improved surface hardness which correlates to Dirt Pick Up Resistance (DPUR). To enhance the performance further, a hydrophobic monomer and an acrylic monomer have been used which will crosslink in presence of sunlight.
In an embodiment of the present disclosure, the emulsion is used as a binder for high performance exterior coating composition.
In still another aspect, the present disclosure provides a coating composition comprising the emulsion in an amount in the range of 10 mass% to 60 mass%; a pigment in an amount in the range of 5 mass% to 30 mass%; an extender in an amount in the range of 1 mass% to 10 mass%; additives in an amount in the range of 0.5 mass % to 10 mass%; wherein the mass% are with respect to the total mass of the coating composition.
In an exemplary embodiment of the present disclosure, a coating composition comprising emulsion in an amount of 50 mass%, a pigment in an amount of 30 mass%, an extender in an amount of 10 mass%, additives in an amount of 10 mass %, wherein the mass% are with respect to the total mass of the coating composition.
In an embodiment of the present disclosure, the pigment is selected from the group consisting of titanium dioxide, anatase, and rutile. In an exemplary embodiment of the present disclosure, the pigment is titanium dioxide.
In an embodiment of the present disclosure, the rutile is rutile surface treated with Alumina /Silica /Zirconia.
In an embodiment of the present disclosure, the extender is selected from the group consisting of talc, and calcium carbonate. In an exemplary embodiment of the present disclosure, the extender is talc.
In an embodiment of the present disclosure, the additives are selected from the group consisting of silane based additives, fluro based additives, and preservatives. In an exemplary embodiment of the present disclosure, the additive is silane based additives.
In an embodiment of the present disclosure the, preservative is at least one selected from in can preservative and dry film preservative.
In an embodiment of the present disclosure, the in can preservative and dry preservation are independently selected from the group consisting of CIT/MIT (Methyl Chloroisothiozolinone and Methylisothiozolinone), CMIT, Benzisothiazolinone (BIT). In an exemplary embodiment of the present disclosure, the dry film preservative is combination of CIT/ MIT (3:1) and BIT.
In an embodiment of the present disclosure, the coating composition is characterized by having a Viscosity in the range of 15000 cps to 19000 cps and a pigment volume concentration in the range of 30 mass% to 35 mass%. In an exemplary embodiment of the present disclosure, the coating composition characterized by having a Viscosity in the range of 16350 cps and a pigment volume concentration of 35 mass%.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment but are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further described in light of the following experiments which are set forth for illustration purpose only and not to be construed for limiting the scope of the disclosure. The following experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial scale.
EXPERIMENTAL DETAILS
Experiment 1: Process for the preparation of an emulsion in accordance with the present disclosure.
I. Preparation of reactor charge mixture in accordance with the present disclosure.
15.5 kg of demineralized water, 0.3 kg of alpha olefin sulfonate (anionic surfactant), 0.2 kg of fatty alcohol ethoxylate (non-ionic surfactant), 2.67 kg of sodium bicarbonate solution (buffer solution) (0.17 kg sodium bicarbonate in 2.5 kg of demineralized water) were charged in a reactor and heated to 83 °C to 85 °C for 50 minutes to obtain a reactor charge mixture.
II. Preparation of pre-emulsions in accordance with the present disclosure.

a) Preparation of a first pre-emulsion
13.3 kg of demineralized water, 0.4 kg of alpha olefin sulfonate (anionic surfactant), 0.4 kg of fatty alcohol ethoxylate (non-ionic surfactant), 14 kg of methyl metha acrylate (hard monomer), 12 kg of butyl acrylate (soft monomer), 0.5 kg of MMA (carboxy functional monomer) were mixed at 30 ºC (room temperature) for 1 hour and 30 minutes to obtain a first pre-emulsion.
0.3 kg of vinyl trimethoxy silane (silane functional monomer) was added after 1 hour in the first pre-emulsion.
b) Preparation of a second pre-emulsion
6.5 kg of demineralized water, 0.4 g of alpha olefin sulfonate (anionic surfactant), 0.4 kg of fatty alcohol ethoxylate (non-ionic surfactant), 5.5 kg of methyl meth acrylate (hard monomer), 6.5 kg of butyl acrylate (soft monomer), 8 kg of vinyl neodecanoate (speciality monomer), 1.5 kg of HEMA (hydroxyl functional monomer), 0.3 kg of MMA (carboxy functional monomer), 0.5 kg of 2,2,4-trimethyl-1,3-pentanediol di isobutyrate (coalescing agent), and 5 kg of dimethylamino ethyl methacrylate (functional monomer-UVcrosslinking) were mixed at 30 ºC (room temperature) for 1 hour and 15 minutes to obtain a second pre-emulsion.
0.1 kg of vinyl trimethoxy silane (silane functional monomer) was added after 1 hour in the second pre-emulsion.
• Sequential addition of the first pre-emulsion followed by the second pre-emulsion in the reactor charge mixture.

i) Addition of first pre-emulsion in the reactor charge mixture.
8 kg of the first pre-emulsion obtained in step II (a) and 2.63 kg of the potassium persulphate solution (first portion of initiator solution) (0.13 kg of potassium persulphate in 2.5 kg of water) was added to the reactor charge mixture obtained in step I (initially the temperature will drop to 75 ºC and as the reaction starts it will start increasing. It is ensured that complete exotherm is achieved and temperature stabilizes) and further 92 kg of the first pre-emulsion was added at a rate of 16.28 g/min and mixed for 2.5 hours by maintaining a temperature of 83 °C to 85 °C to obtain a first pre-emulsified mixture.
0.9 kg of potassium persulphate solution (second portion of initiator solution) (0.1 kg of potassium persulphate in 0.8 kg of water) was added to the first pre-emulsion just before adding the first pre-emulsion to the reactor charge mixture.
ii) Sequential addition of second pre-emulsion
The second pre-emulsion obtained in the step II (b) was added to the first pre-emulsified mixture obtained in step II (i) at a rate of 20.16 g/min by maintaining the temperature of the reactor of 83 °C to 85 °C for 1.5 hours to obtain a second pre-emulsified mixture.
0.55 kg of potassium persulphate solution (third portion of initiator solution) (0.05 kg of potassium persulphate in 0.5kg of water) was added to the second pre-emulsion (just before adding the second pre-emulsion to the first emulsified mixture).
III. Addition of redox initiators
The second pre-emulsified mixture obtained step II (ii) was maintained at 83 °C to 85 °C for 15 minutes followed by cooling 75 °C to obtain an intermediate mixture.
0.62 kg of first redox initiator solution (comprising 0.04 kg of tert-Butyl hydroperoxide (first redox initiator), 0.1 kg of fatty alcohol ethoxylate (non-ionic surfactant) and 0.48 kg of demineralized water) was added to the intermediate mixture at 75 °C for 10 minutes followed by adding 1.04 kg of second redox initiator solution (comprising 0.04 kg of Sodium formaldehydesulfoxylate in 1 kg of water) for 10 minutes to obtain a first resultant mixture.
The first resultant mixture was maintained at a temperature of 75 °C for 50 minutes followed by cooling to 45 °C to obtain a second resultant mixture.
IV. Addition of additives
In the so obtained second resultant mixture, 0.91 kg of liquid ammonia solution (neutralizing agent) (0.75 kg of liquid ammonia in 0.16 kg of water) was mixed for 10 min followed by mixing 0.45 kg of CIT solution (preservative) (0.15 kg of CIT in 0.3 kg of water) for 10 min, 0.3 kg of Sanitize BT 10A solution (0.1 kg of Sanitize BT 10A in 0.2 kg of water) for 10 min, 0.164 kg of tegofoamex K3 solution (0.004 kg of tegofoamex K3 in 2.4 kg of water) for 10 minutes to obtain the emulsion.
Table 1 demonstrates the composition of the emulsion prepared in accordance with the present disclosure and the comparative example.
Table 1: Components and amounts of components used in the preparation of emulsion in accordance with the present disclosure.
Sr. No. Functionality of the Components of emulsion Specific Components Experiment 1
(kg) Comparative Example
1 Continuous Phase for Polymerization D M Water 46.56 46.56
2 For emulsification of monomer Surfactant – Anionic – Alpha Olefin Sulfonate (Kemsurf OS 38) 1.2 1.2
3 For emulsification of monomers Surfactant – Non-ionic – Fatty alcohol Ethoxylate (ATSURF G 140/70) 1 1
4 Hard Monomer Methyl Methacrylate 19.5 24
5 Soft Monomer Butyl Acrylate 18.5 15
6 Functional Monomer Methacrylic Acid, HEMA, Visiomer6976, Silane A-171 3.2 3.2
7 Speciality Monomer Veova 10 (Hexion) Vinyl neodecanoate 8 0
2 -Ethyl Hexyl acrylate 0 7
8 Initiator Potassium per sulphate, TBHP, SFS 0.36 0.36
9 Buffer Sodium Bicarbonate 0.17 0.17
10 Coalescing Agent OE300 0.5 0.5
11 Liquid ammonia Neutralizer 0.75 0.75
12 Incan preservative – Quick kill CIT / CMIT (Sanitized CI15)+ BIT (Sanitized BT 10 A) 0.25 0.25
13 Defoaming agent Tegofoamex K 3 0.004 0.004
Total 99.9 99.9
From Table 1 it was observed that the emulsion of comparative example consists 2 -Ethyl Hexyl acrylate instead of Veova 10 (Hexion) Vinyl neodecanoate.
Characteristics of the emulsion prepared in accordance with the present disclosure.
The characteristics of the emulsion prepared in accordance with the present disclosure are summarized in Table 2.
The water resistance of the emulsion was measured by apply the emulsion using 4 mill applicator on a glass plate such that the dry film thickness of emulsion film will be close to 40 -50 microns. Dry the film at RT (27 ºC & 60 RH) for 1 day. Then dip it into water such that 40- 50% film is dipped in water. Observe for water resistance after 24 hours visually.
Table 2: Characteristics of the emulsion prepared in accordance with the present disclosure.
Sr No Properties Emulsion prepared in accordance with the present disclosure Comparative emulsion
1 Appearance Bluish White Emulsion Bluish White Emulsion
2 % NVM At 120 ºC for 1 hr 50.10% 50.05%
3 Viscosity 3rd spindle 60 rpm in cps 485 553
4 pH 9.10 9.23
5 Electrolytic Stability / 100 gm sample Passes 10 ml Passes 10 ml
6 Particle Size in nm (using the Horiba - Light scattering particle size distribution analyzer LA 950) 0.087 0.091
7 Water Resistance R=4 R=3
8 MFFT in ºC (using the Rhopoint MFFT Bar using 76 µ applicator under Nitrogen atmosphere) 10 to 11 11 to 12
9 Dry Film properties (Application on Paper panel at 100 Mic WFT)
Tack Non Tacky Non Tacky
Bits No Bits No Bits
Clarity Clear Clear
From Table 2 it was observed that the water resistance of the comparative emulsion is lower as compared to the water resistance of the emulsion prepared in accordance with the present disclosure. The water resistance correlates with the better adhesion, resistance to blistering and better water proofing performance. Thus, the emulsion prepared in accordance with the present disclosure will have better adhesion, resistance to blistering and better water proofing performance as compared to the comparative emulsion.
Experiment 2: Preparation of coating composition
Example (i): Coating composition by using the emulsion prepared in the example 1 of the present disclosure.
50 kg of the emulsion obtained in experiment 1, 30 kg of titanium dioxide (pigment) , 10 kg of talc (extender), 5 kg of CIT/ MIT, BIT (preservative), and 5 kg of Epoxy Silane / Amino Silane Polymer (silane based additives) were mixed for 2 hours to obtain the coating composition.
Comparative Example: Coating composition by using the emulsion prepared in the comparative example
A coating composition was prepared by using the same process of Example (i) except the emulsion of the comparative example of Experiment 1 was used.
Characteristics of the coating composition prepared in accordance with the present disclosure.
The coating composition obtained in experiment 2 was subjected for characterization.
a) Physical properties of the coating composition of the present disclosure:
The coating composition prepared in accordance with the present disclosure was subjected for the evaluation of physical properties.
The viscosity of the coating composition was measured by using Brookfield viscometer DV1-Using Spindle 3 at 60 rpm.
The tint strength was measured by ASTM D2745-00. The results are summarized in table 3.
Table 3: Physical properties of the coating compositions.
Sr. No. Properties Standard Coating composition of the present disclosure Comparative Coating Composition
Experiment 1 *Repeat experiment 1
1 In can appearance STANDARD Comparable
2 solids 59% 60.03% 59.08% 59.10%
3

**Viscosity in cps(Initial) 15200cps 15100cps 15250cps 15450cps
Viscosity in cps(ON) 16300Cps 16350Cps 16250cps 16550cps
Viscosity in cps(after incubation) 19750cps 19200cps 19500cps 19300cps
4 Tint Strength (%) STANDARD 82.33% 81.06% 89.06%
5 Delta E 2.37 2.63 2.63
*Repeat experiment 1refers to repeating the same experiment 1 on the same sample to verify the results.
**Viscosity (Initial/ON/after incubation) are the viscosities tested at different time span such as Initially - Means immediately after preparation, ON – Means after 24 hours of preparation; and After Incubation - Means after keeping at 60 ºC in oven for 10 days.
From table 3 it was observed that the Viscosity (Initial/ON/after incubation of the comparative coating composition is higher than the standard viscosities. The higher viscosity may create difficulty while applying the coating composition on the substrate. The viscosities of the coating composition prepared by using the emulsion of the present disclosure are comparable with the standard viscosities.
Further, the tint strength of the comparative coating composition was higher than the tint strength of the coating composition prepared by using the emulsion of the present disclosure. The higher tint strength leads to lower opacity and inferior colour acceptance in the range of 5% to 10%.
Figure 1 illustrates (a) tint strength of the standard coating composition, and (b) tint strength of the coating composition prepared in accordance with the present disclosure (experiment 1). From Figure 1 and table 3 it is observed that the comparative example is having lower overall visual and colouristic coating performance.
b) Optical properties of the coating composition of the present disclosure:
The coating composition prepared in accordance with the present disclosure was subjected for the evaluation of optical properties. The opacity was measured by using Spectro photometer. Further, the coverage of the coating composition was measured by weight deposition method. The results are results are summarized in Table 4.
Table 4: Optical properties of the coating compositions.
Sr. No. Properties Standard Coating composition of the present disclosure Comparative Coating Composition
Experiment 1 Repeat experiment 1
1 Wet visual Standard Comparable to standard Comparable

2 Dry visual Comparable better better
3 W/Litre 1.343 1.343 1.346 1.343
Coverage 47.89sqft 47.21sqft 47.53Sq.ft 47.78sqft
From table 4 it was observed that the dry visual appearance of the film obtained by applying the coating composition in accordance with the experiment 1 and repeat experiment was better that the standard, whereas the dry visual appearance of the film obtained by applying the comparative coating composition was comparable with the standard.
c) Aesthetic properties of the coating composition of the present disclosure:
The coating composition prepared in accordance with the present disclosure was subjected for the evaluation of color properties.
The coating composition was applied on paper panel at 100 Mic WFT followed by cure for 24 hours and coloristic values were measured on a spectrophotometer.
The Yellowness of the coating composition was measured by ASTM E313.
For measuring the gloss/sheen values, the coating composition was applied on a glass plate using 4 mill applicator such that the dry film thickness of the coating composition will be close to 50 microns to obtain a film. Dry the film at 27 °C and 60 RH for 1 day to obtain a dried film. Measure the gloss of the dried film using glossometer. The results are summarized in table 5.
Table 5: Color properties of the coating compositions.
Sr. No. Properties Standard Coating composition of the present disclosure Comparative Coating Composition
Experiment 1 Repeat experiment 1
1 Contrast ratio 93.30 98.2 100 93.45
2 *Tappi Brightness 87.26 88.64 85.35 88.00
3 ASTM E313 Yellowness 3.4 1.34 1.32 3.4
4 Whiteness Index 80.41 83.63 84.27 81.41
5 Finish Smooth Smooth Smooth Smooth
6 Sheen on Glass panel
20°/60°/85° 1.6/6.6/19.2 1.7/6.9/19.2 1.7/6.8/19.3 1.6/6.6/19.2
*Tappi Brightness indicates the opacity/brightness of the coating composition. Higher values indicates good brightness.
Table 5 illustrates the optical properties of the coating film. Tappi brightness measures brightness of the coated film. The higher value is better - indicating better brightness. Yellowness index gives indication of yellowness in the film. Lower value is better indicating lower yellowness in film, better whiteness and shade acceptance. Whiteness measures the whiteness of the film. Higher value is better indicating the improved or better white film. Gloss indicates shininess of the paint film. Similar values or better values gives expected performance.
From table 5 it was observed that the Tappi Brightness of the coating composition of experiment 1 prepared in accordance with the present disclosure is higher than the comparative coating composition which indicates that the film obtained by applying the coating composition of the present disclosure was bright compared to the film obtained by applying the comparative coating composition. Further, the Whiteness Index of the coating composition of experiment 1 prepared in accordance with the present disclosure is higher than the comparative coating composition, which indicates that the coating composition of experiment 1 prepared in accordance with the present disclosure is whiter than the comparative coating composition.
d) Mechanical properties of the film obtained by applying the coating composition of the present disclosure.
The coating composition was subjected for evaluation of the mechanical properties.
For this, the coating composition was applied on a substrate to obtain a film such that the DFT of the film is 100 to 130 micron and cure for 21 days at 30 °C (ambient temperature). Another film of the coating composition was obtained such that DFT of the film was 230 to 270 micron and cure for 21 days at 30 °C (ambient temperature). Universal Tensile Strength Instrument was used to measure elongation and tensile strength.
To measure the wet scrub resistance, the coating composition was applied on lancet panel using 46 mill applicator such that the dry film thickness of the coating composition is close to 50 microns followed by drying at 30 °C and 60 RH for 7 day. Wet scrub resistance was measured on the film using a wet scrub apparatus. The results are summarized in table 6.
Table 6: Mechanical properties of the film obtained by using the coating composition of the present disclosure.
Sr. No. Film having thickness Standard Coating composition of the present disclosure Comparative Coating Composition
Experiment 1 Repeat experiment 1
Elongation% after 21 days
1 Film having DFT
(100-130) 35% 43.7% 44.45% 30%
2 Film having
DFT
(230-270) 34.5% 45.5% 43.25% 33%
Tensile Strength After 21 days in Mpa
3 Film having
DFT
(100-130) 1.67 1.75 1.7 1.6
4 Film having
DFT
(230-270) 1.9 2.10 2.2 1.89
Wet Scrub Resistance
6 Wet Scrub Test (Cycles) 453 430 419 450
From Table 6 it is observed that the mechanical properties of the coating composition of experiment 1 in accordance with the present disclosure such as elongation and tensile strength are better than the standard coating composition and the comparative coating composition. Further, the values of the wet scrub test are comparable with the standard coating composition. The scrub resistance correlates to adhesion of the coating. It means adhesion of the coating is comparable considering experimental variation. Apart from adhesion it also indicates the longitivity of film.
e) Stability test of the coating composition prepared in accordance with the present disclosure.
To evaluate the stability, the coating composition was placed in an incubator at a temperature of 60 °C for 10 days and assessed for any phase separation or particle formation. The results are summarized in table 7.
Table 7: Mechanical properties of the film obtained by using the coating composition of the present disclosure.
Sr. No. Property Standard Coating composition of the present disclosure Coating composition of the present disclosure
Experiment 1 Repeat Experiment 1
1 Separation No No No No
2 Settling No No No No
The settling and separation is measured after oven stability. As there is no separation and settling it indicates that performance is comparable to standard. This is indication of the paint stability. From table 7 it was observed that phase separation or settling was not observed in the coating composition of the present disclosure. The coating composition was found to be satisfactory showing good shelf stability.
f) Dirt pick up resistant of the coating composition prepared in accordance with the present disclosure.
The coating composition prepared in accordance with the present disclosure was subjected for the evaluation of Dirt pick up resistance.
To measure the dirt pick up resistance the coating composition of the present disclosure was applied on paper panel at 100 Mic WFT and cured for 15 days at 30 °C (ambient temperature condition) to obtain a film. Activated charcoals were sprinkled on the film and give 20 cycles.
Figure 2 illustrates DPUR results of the (a) of the standard coating composition, of the coating composition prepared in accordance with the present disclosure (experiment 1). It was observed that Dirt Pick up Resistance after 15 days of curing of the film obtained by the coating composition of the present disclosure was better (it attracts less black colour from the charcoal) than the standard.
g) QUV / UV Exposure (Weathering studies) of the films prepared using the coating composition prepared in accordance with the present disclosure.
The coating composition was subjected for weathering test to evaluate the QUV / UV Exposure of the film.
The coating composition was diluted by 35% with water followed by applying two coats of the coating composition on the test panel such that DFT of the film is in the range of 110 to 120 microns. The film was cured for 7 days at 30 °C (ambient temperature) and tested in QUV FS 40. The results are summarized in table 8.
The coated panels were exposed for 600 hours to UV radiation followed by measuring the l, a, b values against the standard. It was observed that the values are lower. Theoretically the values should be lower which indicates that the paint has impacted less by the UV Chamber conditions.
The test was continued for 1500 hours to get impact of chamber condition after prolonged time and the l, a, b values are inline with previous results.
QUV test indicatively correlates to the exterior durability under natural exposure.
Table 8: QUV / UV Exposure (Weathering studies) of the films prepared using the coating composition prepared in accordance with the present disclosure.
Sr. No. Property Standard Coating composition of the present disclosure
Experiment 1 Repeat Experiment 1
1 QUV / UV Exposure (checked up to 600 Hours). Best Results are Comparable to or Better than the standard Results are Comparable to or Better than the standard
2 QUV / UV Exposure (checked up to 1500 Hours) Results are Comparable to or Better than the standard Results are Comparable to or Better than the standard
Figure 3 illustrates QUV results after 1500 hours (a) of the standard coating composition, of the coating composition prepared in accordance with the present disclosure (experiment 1) and of the coating composition prepared in accordance with the present disclosure (experiment 2).
Shade fading, gloss retention, resistance to chalking and film integrity is checked. Film integrity means flaking /cracking. It is less or comparable.
The QUV performance correlates to exterior exposure after actual coating application. The performance was comparable or better than the standard coating composition.
From Figure 3 and table 8 it was observed that the coating composition of experiment 1 is less impacted by the UV Chamber conditions.
h) Anti-microbial/fungal/algal resistance the coating composition prepared in accordance with the present disclosure.
The coating composition was evaluated for anti-bacterial/fungal/microbial resistance by as per ASTM D 5589 and ASTM D 908.
It was observed that the coating composition of the present disclosure passes the test.
Further, it was observed that the finish of the coating composition of the present disclosure after incubation was smooth without any bits.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of;
? an emulsion that can be used in a coating composition that;
• has high dirt-pickup resistance (DPUR);
• has high elongation;
• has high tensile strength;
• is economic and environment friendly; and
? a process for the preparation of an emulsion that;
• is simple, economic, efficient and environmental friendly.
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising, will be understood to imply the inclusion of a stated element, integer or step,” or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
The numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.
While considerable emphasis has been placed herein on the specific features of the preferred embodiment, it will be appreciated that many additional features can be added and that many changes can be made in the preferred embodiment without departing from the principles of the disclosure. These and other changes in the preferred embodiment of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. , C , C ,
Claims:WE CLAIM:
1. An emulsion being a reaction product of:
a. monomers selected from a hard monomer, a soft monomer, a speciality monomer, and a functional monomer;
b. an initiator;
c. a surfactant;
d. an additive; and
e. water.
2. The emulsion as claimed in claim 1 comprises:
a. 10 mass% to 30 mass% of said hard monomer;
b. 10 mass% to 20 mass % of said soft monomer;
c. 0.2 mass% to 10 mass% of said speciality monomer;
d. 0.5 mass% to 5 mass% of said functional monomer;
e. 0.1 mass% to 1 mass% of said initiator;
f. 1 mass% to 5 mass% of said surfactant;
g. 0.1 mass% to 5 mass% of said additive; and
h. q.s. water,
wherein the mass% of each component is with respect to the total mass of said emulsion.
3. The emulsion as claimed in claim 1, wherein said hard monomer is selected from the group consisting of methyl methacrylate, styrene, cyclohexyl methacrylate (CHMA), and tert-butyl acrylate (TBA).
4. The emulsion as claimed in claim 1, wherein said soft monomer is selected from the group consisting of butyl acrylate, ethyl hexyl acrylate, vinyl neodecanoate, and ethyl acrylate.
5. The emulsion as claimed in claim 1, wherein said speciality monomer is selected from the group consisting of vinyl neodecanoate, benzophenone methacrylate mixture, and silane monomer.
6. The emulsion as claimed in claim 1, wherein said functional monomer is selected from the group consisting of methacrylic acid, hydroxyl ethyl methacrylate, dimethyl amino ethyl methacrylate and vinyl trimethoxy silane.
7. The emulsion as claimed in claim 1, wherein said initiator is selected from the group consisting of potassium persulfate, ammonium per sulfate, and sodium persulfate, a first redox initiator and a second redox initiator, wherein
• said first redox initiator and said second redox initiator are independently selected from the group consisting of tert-butyl hydroperoxide, sodium formaldehydesulfoxylate, tert-butyl hydroperoxide, sodium formaldehydesulfoxylate/Fe (III), ammonium persulfate, sodium bisulfite, sodium hydrosulfite/ Fe(III).
8. The emulsion as claimed in claim 1, wherein said surfactant is selected from the group consisting of an anionic surfactant and non-ionic surfactant;
wherein said anionic surfactant is selected from the group consisting of alpha olefin sulfonate, sodium lauryl ethers, alkyl diphenyloxide disulfonate, disodium ethoxylated alcohol half ester of succinic acid, and alkyl aryl sulfonates; and
said non-ionic surfactant is selected from the group consisting of fatty alcohol ethoxylate, trididecyl alcohol ethoxylate, linear C9-C11 alcohol ethoxylate, and synthetic C12-C15 alcohol ethoxylate.
9. The emulsion as claimed in claim 1, wherein said additive is selected from the group consisting of a buffer, a coalescing agent, a preservative, a defoaming agent, and a neutralizing agent.
10. The emulsion as claimed in claim 9, wherein
• said buffer is selected from the group consisting of sodium bicarbonate, sodium acetate, and sodium carbonate;
• said preservative is selected from the group consisting of 5-Chloro-2-methyl-4-isothiazolinone-3-one and 2-Methyl-4-isothiazolinone-3-one CMIT/MIT, and 1,2-Benzisothiazol-3(2H)-one (BIT).
• said neutralizing agent is selected from the group consisting of liquid ammonia, sodium hydroxide, and a mixture of organic amine;
• said coalescing agent is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, and 3- hydroxy-2,2,4- trimethyl pentyl isobutyrate; and
• said defoaming agent is selected from the group consist of tegofoamex k3, and mineral oil based defoamer.
11. The emulsion as claimed in claim 1 is characterized by having
• a nonvolatile matter in the range of 45 % to 55%;
• viscosity in the range of 200 cps to 900 cps; and
• minimum film forming temperature in the range of 10 °C to 15 °C
12. A process for the preparation of an emulsion, said process comprising the following steps:
i) charging first portions of water, surfactants and a predetermined amount of a buffer solution in a reactor under stirring followed by heating at a temperature in the range of 80 °C to 90 °C for a time period in the range of 20 minutes to 2 hours to obtain a reactor charge mixture;
ii) separately, mixing second portions of water, surfactants and a first portion of monomers at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a first pre-emulsion;
iii) separately, mixing third portions of water, surfactants, a second portion of monomers and a predetermined amount of coalescing agent at a temperature in the range of 25 ºC to 35 ºC (room temperature) for a time period in the range of 20 minutes to 2 hours to obtain a second pre-emulsion;
iv) adding a first portion of said first pre-emulsion, followed by adding a first portion of a initiator solution to said reactor charge mixture and further adding a second portion of said first pre-emulsion and mixing for a time period in the range of 2 hours to 3 hours by maintaining said temperature of said reactor in the range of 80 ºC to 90 ºC to obtain a first pre-emulsified mixture,
wherein a second portion of said initiator solution is added to said first pre-emulsion just before adding said first pre-emulsion to said reactor charge mixture;
v) adding said second pre-emulsion to said first pre-emulsified mixture by maintaining said temperature of said reactor in the range of 80 ºC to 90 ºC for a time period in the range of 1 hour to 2 hours to obtain a second pre-emulsified mixture;
wherein a third portion of said initiator solution is added to said second pre-emulsion just before adding said second pre-emulsion to said first pre-emulsified mixture;
vi) maintaining said second pre-emulsified mixture at said temperature of said reactor in the range of 80 °C to 90 °C for a time period in the range of 10 minutes to 20 minutes followed by cooling to a temperature in the range of 70 °C to 78 °C to obtain an intermediate mixture;
vii) adding a predetermined amount of a first redox initiator solution in said intermediate mixture by maintaining said reactor at said temperature in the range of 70 °C to 78 °C for a time period in the range of 5 minutes to 15 minutes followed by adding a predetermined amount of a second redox initiator solution for a time period in the range of 5 minutes to 15 minutes to obtain a first resultant mixture;
viii) maintaining said resultant mixture at a temperature in the range of 70 °C to 78 °C for a time period in the range of 40 minutes to 60 minutes followed by cooling to a temperature of 40 °C to 50 °C to obtain a second resultant mixture; and
ix) adding predetermined amount of additives to said second resultant mixture under stirring for a time period in the range of 20 minutes to 3 hours to obtain said emulsion.
13. The process as claimed in claim 12, wherein
• said first portion of said water is in the range of 10 mass% to 20 mass%;
• said first portion of said surfactant is in the range of 0.4 mass% to 1 mass%; and
• said predetermined amount of buffer is in the range of 0.05 mass% to 0.3 mass%;
wherein said mass% of each ingredient is with respect to the mass % of said emulsion.
14. The process as claimed in claim 12, wherein said first portion, said second portion and said third portion of surfactants are independently selected from the group consisting of an anionic surfactant and non-ionic surfactant;
• wherein said anionic surfactant is selected from the group consisting of alpha olefin sulfonate, sodium lauryl ethers, alkyl diphenyloxide disulfonate, disodium ethoxylated alcohol half ester of succinic acid, alkyl aryl sulfonates; and
• said non-ionic surfactant is selected from the group consisting of fatty alcohol ethoxylate, trididecyl alcohol ethoxylate, linear C9-C11 alcohol ethoxylate, and synthetic C12-C15 alcohol ethoxylate.
15. The process as claimed in claim 12, wherein said buffer is selected from the group consisting of sodium bicarbonate, sodium acetate, and sodium carbonate.
16. The process as claimed in claim 12, wherein
• said second portion of said water is in the range of 10 mass% to 20 mass%;
• said second portion of said surfactants is in the range of 0.4 mass% to 1.5 mass%; and
• said first portion of said monomers is in the range of 20 mass% to 30 mass%;
wherein said mass% of each ingredient is with respect to the mass % of said emulsion.
17. The process as claimed in claim 12, wherein said first portion of said monomers and said second portion of said monomers are independently selected from the group consisting of a hard monomer, a soft monomer, a speciality monomer, and a functional monomer.
18. The process as claimed in claim 17, wherein
• said hard monomer is selected from the group consisting of methyl methacrylate, styrene, cyclohexyl methacrylate (CHMA), and tert-butyl acrylate (TBA);
• said soft monomer is selected from the group consisting of butyl acrylate, ethyl hexyl acrylate, vinyl neodecanoate, and ethyl acrylate; and
• said functional monomer is selected from the group consisting of methacrylic acid, vinyl trimethoxy silane, hydroxyl ethyl methacrylate, and dimethyl amino ethyl methacrylate.
19. The process as claimed in claim 12 and claim 18, wherein said at least one functional monomers are added in said first pre-emulsion and said second pre-emulsion after a time period in the range of 45 minutes to 85 minutes.
20. The process as claimed in claim 12, wherein
• said first portion of said initiator solution is in the range of 2 mass% to 3 mass% with respect to the total mass of said emulsion;
• said second portion of said initiator solution is in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of said emulsion;
• said third portion of said initiator solution is in the range of 0.1 mass% to 1 mass% with respect to the total mass of said emulsion; and
• said initiator is selected from the group consisting of potassium persulfate, ammonium per sulfate, and sodium persulfate.
21. The process as claimed in claim 12, wherein said first pre-emulsion is added at a rate of 10 g/min to 20/g/min and said second pre-emulsion is added at rate of 15 g/min to 25/g/min.
22. The process as claimed in claim 12, wherein said first portion of said first pre-emulsion is in the range of 5 mass% to 10 mass% with respect to total mass of said first pre-emulsion and said second portion of said first pre-emulsion is in the range of 90 mass% to 95 mass% with respect to total mass of said first pre-emulsion.
23. The process as claimed in claim 12, wherein
• said third portion of water is in the range of 5 mass% to 10 mass%;
• said third portion of surfactants is in the range of 0.5 mass% to 1.5 mass%;
• said second portion of monomer is in the range of 20 mass% to 25 mass%;
• said predetermined amount of coalescing agent is in the range of 0.1 mass% to 1 mass%;
• said third portion of said initiator is in the range of 0.01 mass% to 0.1 mass%;
wherein said mass% of each ingredient is with respect to the mass % of said emulsion.
24. The process as claimed in claim 12, wherein
• said predetermined amount of said first redox initiator solution is in the range of 0.5 mass% to 1 mass% with respect to the total mass of said emulsion; and
• said predetermined amount of said second redox initiator solution is in the range of 0.5 mass% to 1.5 mass% with respect to the total mass of said emulsion.
25. The process as claimed in claim 24, wherein said first redox initiator and said second redox initiator are independently selected from the group consisting of tert-butyl hydroperoxide, sodium formaldehydesulfoxylate, tert-butyl hydroperoxide, sodium formaldehydesulfoxylate/Fe (III), ammonium persulfate, sodium bisulfite, sodium hydrosulfite/ Fe(III).
26. The process as claimed in claim 12, wherein said predetermined amount of additive is in the range of 0.1 mass% to 5 mass% with respect to the total mass of the emulsion.
27. The process as claimed in claim 12, wherein said each additive is separately mixed in a predetermined amount of water followed by stirring for time period in the range of 5 minutes to 15 minutes, and wherein said predetermined amount of water is in the range of 2.5 mass% to 3.5 mass% with respect to the total mass of said emulsion.
28. The process as claimed in claim 12, wherein said additive is selected from the group consisting of a buffer, a preservative, a defoaming agent, coalescing agent and a neutralizing agent.
29. The process as claimed in claim 28, wherein
• said buffer is selected from the group consisting of sodium bicarbonate, sodium acetate, sodium carbonate;
• said preservative is selected from the group consisting of CIT/CMIT (Sanitized CI15), and BIT (Sanitized BT 10 A);
• said neutralizing agent is selected from the group consisting of liquid ammonia, sodium hydroxide, and mixture of organic amine;
• said coalescing agent is selected from the group consisting of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, 3- hydroxy-2,2,4- trimethyl pentyl Isobutyrate; and
• said defoaming agent is selected from the group consist of tegofoamex k3, Mineral Oil based defoamer.
30. A coating composition comprising,
• said emulsion as claimed in claim 1 in an amount in the range of 10 mass% to 60 mass%;
• a pigment in an amount in the range of 5 mass% to 30 mass%;
• an extender in an amount in the range of 1mass% to 10 mass%;
• additives in an amount in the range of 0.5 mass % to 10 mass%;
wherein said mass% are with respect to the total mass of the coating composition.
31. The coating composition a claimed in claim 30, wherein
• said pigment is selected from the group consisting of titanium dioxide, anatase, and rutile;
• said extender is selected from the group consisting of talc and calcium carbonate; and
• said additive is selected from the group consisting of fluro based additives, silane based additives, and preservatives.
32. The coating composition as claimed in claim 30 is characterized by having a viscosity in the range of 15000 cps to 19000 cps and pigment volume concentration in the range of 30 mass% to 35 mass%.

Dated this 7th day of May, 2024

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
OF R. K. DEWAN & CO.
AUTHORIZED AGENT OF APPLICANT