Description:FIELD
The present disclosure relates to an elastomeric emulsion and a process for its preparation.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Commonly, water leakages or water seepages are seen in many constructed buildings. The probable cause of seepage or leakage is water penetration through external wall defects such as cracks, holes, and the like.
Conventionally, urethane-epoxy polymers, acrylic polymers, polyurethanes and polyurethane modified with polyacrylates are used for waterproofing coating. The polyurethane modified with polyacrylates are the most preferred ones. Two methods can be used to modify polyurethane with polyacrylates: physical methods and chemical methods. In the physical method, aqueous polyacrylates and polyurethane dispersions (emulsions) are independently prepared first, and then both dispersions are mixed together under mechanical mixing to obtain a blend. However, in such blends, the superior performance properties may be compromised because of the incompatibility of the two materials, polyurethanes and polyacrylates. Further, such blends may suffer from instability.
In the chemical method, the polyurethane dispersion is prepared first, and then acrylates and other vinyl monomers are polymerized in the polyurethane dispersion. However, when polyurethane/acrylic hybrid dispersions made according to the chemical method are formulated into paints with a pigment volume concentration (PVC) exceeding 40%, the elongation of coatings made therewith drops dramatically. Further, the polyurethane-polyacrylate hybrid dispersions suffer from the disadvantage of insufficient filler compatibility when this hybrid is employed in paints having high filler content.
There is, therefore, felt a need to provide an elastomeric emulsion that mitigates the aforestated drawbacks or at least provides a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to ameliorate one or more problems of the background or to at least provide a useful alternative.
An object of the present disclosure is to provide an elastomeric emulsion.
Another object of the present disclosure is to provide an elastomeric emulsion that has excellent water and alkali resistant properties.
Still another object of the present disclosure is to provide an elastomeric emulsion that has excellent anti-efflorescence properties.
Yet another object of the present disclosure is to provide an elastomeric emulsion that achieves desirable tensile strength and higher elongation in the cementitious waterproofing membrane application.
Still another object of the present disclosure is to provide a simple and efficient process for the preparation of an elastomeric 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 elastomeric emulsion being a reaction product of monomers selected from at least one styrene monomer and at least one acrylate monomer, a polyurethane compound, at least one initiator, at least one buffering agent, at least one surfactant, at least one first additive, at least one second additive and a fluid medium.
In an embodiment of the present disclosure, the styrene monomer is in an amount in the range of 5 mass% to 30 mass%; the acrylate monomer is in an amount in the range of 20 mass% to 70 mass%; the polyurethane compound is in an amount in the range of 1 mass% to 5 mass%; the initiator is in an amount in the range of 0.1 mass% to 1 mass%; the buffering agent is in an amount in the range of 0.05 mass% to 1 mass%; the surfactant is in an amount in the range of 1 mass% to 5 mass%; the first additive is in an amount in the range of 0.1 mass% to 1 mass%; the second additive is in an amount in the range of 0.1 mass% to 1 mass%; and q.s. fluid medium, wherein mass% of each component is with respect to the total mass of the emulsion.
In a preferred embodiment of the present disclosure, the styrene monomer is in an amount in the range of 10 mass% to 30 mass%; the acrylate monomer is in an amount in the range of 30 mass% to 70 mass%; the polyurethane compound is in an amount in the range of 3 mass% to 4 mass%; the initiator is in an amount in the range of 0.2 mass% to 0.8 mass%; the buffering agent is in an amount in the range of 0.1 mass% to 0.8 mass%; the surfactant is in an amount in the range of 2 mass% to 3 mass%; the first additive is in an amount in the range of 0.4 mass% to 0.8 mass%; the second additive is in an amount in the range of 0.4 mass% to 0.8 mass%; and the fluid medium is in an amount in the range of 10 mass% to 50 mass%, wherein mass% of each component is with respect to the total mass of the emulsion.
The polyurethane is an anionic aliphatic polyurethane dispersion (Bayhydrol UH 2864).
The acrylate monomer can be at least one selected from the group consisting of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA), methacrylic acid (MAA), methyl methacrylate (MMA), isobornyl acrylate, isobornyl methacrylate, cyclohexyl methacrylate, 2-ethyl hexyl acrylate (2EHA) and isobutyl acrylate.
The initiator can be at least one selected from the group consisting of potassium per sulfate (PPS), ammonium persulphate and sodium persulphate.
The buffering agent is sodium bicarbonate.
The surfactant can be at least one selected from the group consisting of an anionic surfactant and a nonionic surfactant.
The anionic surfactant is selected from the group consisting of sodium laureth sulfate (SLS), alkyldiphenyloxide Disulfonate (Dowfax 2A1) and ammonium phosphate, polyoxyethylene tridecyl ether (Rhodafac rs 610 A25).
The nonionic surfactant can be at least one selected from the group consisting of Alcohol polyglycol ethers (Spectra TY) and alcohol ethoxylate (ATPOL 5720 -AS-LQ-TH, ATPOL-5731/70N).
The first additive can be at least one selected from the group consisting of tert-Butyl hydroperoxide (TBHP) and sodium formaldehydesulfoxylate (SFS).
The second additive can be at least one selected from the group consisting of a preservative and a neutralizing agent.
The neutralizing agent can be at least one selected from the group consisting of ammonia, sodium hydroxide, 2-amino-2-methyl-1-propanol (AMP-95), Mono ethanol amine (MEA).
The preservative can be at least one selected from the group consisting of a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX150), Chlor-methyl and methyl isothiazolinone (NIPACIDE CI 15 MV), mixture of sodium nitrate, 5-chloro-2-methyl-2H-isothiazol-3one and 2-methyl-2H-isothiazol-3-one (PREVENTOL D7 LT) .
The fluid medium in accordance with the present disclosure is water.
In accordance with the present disclosure, the emulsion is having a core shell structure.
The mass ratio of polyurethane compound to the monomers in the emulsion is in the range of 1:10 to 1:30.
In accordance with the present disclosure, a total solid content of the emulsion is in the range of 50 wt% to 60 wt%.
Further, the present disclosure relates to a process for the preparation of an elastomeric emulsion. The process comprises the step of mixing predetermined amounts of at least one surfactant, at least one polyurethane compound, at least one buffering agent in a predetermined amount of a fluid medium to obtain a first mixture. The first mixture is heated to a first predetermined temperature under stirring at a predetermined stirring speed for a first predetermined time period to obtain a heated first mixture. Separately, an initiator solution is prepared by mixing a predetermined amount of at least one initiator in a predetermined amount of a fluid medium. Separately, a pre-emulsion solution is prepared by mixing predetermined amounts of at least one acrylate monomer, at least one styrene monomer, at least one initiator and at least one surfactant in a predetermined amount of the fluid medium. A predetermined amount of the initiator solution is added to the heated first mixture followed by addition of a predetermined amount of the pre-emulsion solution over a second predetermined time period to obtain a second mixture. A predetermined amount of at least one first additive is added while maintaining the first predetermined temperature for a third predetermined time period to obtain a third mixture. The third mixture is cooled to a second predetermined temperature to obtain a cooled third mixture. A predetermined amount of at least one second additive is added to the cooled third mixture to obtain an emulsion. The emulsion is filtered to obtain an elastomeric emulsion.
In accordance with the present disclosure, the first predetermined temperature is in the range of 70°C to 90°C.
In accordance with the present disclosure, the second predetermined temperature is in the range of 25°C to 35°C.
In accordance with the present disclosure, the predetermined stirring speed is in the range of 100 rpm to 300 rpm.
In accordance with the present disclosure, the first predetermined time period is in the range of 10 minutes to 30 minutes.
The second predetermined time period in accordance with the present disclosure is in the range of 200 minutes to 300 minutes.
In accordance with the present disclosure, the third predetermined time period is in the range of 30 minutes to 70 minutes.
DETAILED DESCRIPTION
The present disclosure relates to an elastomeric emulsion and a process for its preparation.
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.
Waterproofing materials can be additive compounds admixed into plastic concrete to reduce water permeability characteristics. They can be external specific materials like polyvinyl chloride (PVC) rolls, APP membrane, and bituminous-based products applied internally or externally to the entire area to be waterproofed. The conventional polyurethane (PU) liquid waterproofing has a short pot life and needs the application of more than one layer. Bad weather will result in a longer time to apply second layers. Moreover, the protective coating of polyurethane reduces concrete breathing ability as well as is costly. The conventional styrene-acrylic polymers have the tendency to yellowing from direct sunlight exposure. Free radical initiators from polymerization of styrene-acrylic copolymers may influence the degree of yellowing in the final product.
Therefore, the present disclosure provides an elastomeric emulsion which is compatible with cement and can be used to eliminate water seepage or leakage in the buildings.
In a first aspect, the present disclosure provides an elastomeric emulsion. The elastomeric emulsion is a reaction product of:
i. monomers selected from at least one styrene monomer and at least one acrylate monomer;
ii. a polyurethane compound,
iii. at least one initiator;
iv. at least one buffering agent;
v. at least one surfactant;
vi. at least one first additive;
vii. at least one second additive; and
viii. a fluid medium.
In an embodiment of the present disclosure, the styrene monomer is in an amount in the range of 5 mass% to 30 mass%; the acrylate monomer is in an amount in the range of 20 mass% to 70 mass%; the polyurethane compound is in an amount in the range of 1 mass% to 5 mass%; the initiator is in an amount in the range of 0.1 mass% to 1 mass%; the buffering agent is in an amount in the range of 0.05 mass% to 1 mass%; the surfactant is in an amount in the range of 1 mass% to 5 mass%; the first additive is in an amount in the range of 0.1 mass% to 1 mass%; the second additive is in an amount in the range of 0.1 mass% to 1 mass%; and q.s. fluid medium, wherein mass% of each component is with respect to the total mass of the emulsion.
In a preferred embodiment of the present disclosure, the styrene monomer is in an amount in the range of 10 mass% to 30 mass%; the acrylate monomer is in an amount in the range of 30 mass% to 70 mass%;the polyurethane compound is in an amount in the range of 3 mass% to 4 mass%; the initiator is in an amount in the range of 0.2 mass% to 0.8 mass%; the buffering agent is in an amount in the range of 0.1 mass% to 0.8 mass%; the surfactant is in an amount in the range of 2 mass% to 3 mass%; the first additive is in an amount in the range of 0.4 mass% to 0.8 mass%; the second additive is in an amount in the range of 0.4 mass% to 0.8 mass%; and the fluid medium is in an amount in the range of 10 mass% to 50 mass%, wherein mass% of each component is with respect to the total mass of the emulsion.
The acrylate monomer can be at least one selected from the group consisting of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA), methacrylic acid (MAA), methyl methacrylate (MMA), isobornyl acrylate, isobornyl methacrylate, cyclohexyl methacrylate, 2-ethyl hexyl acrylate (2EHA) and isobutyl acrylate. In an exemplary embodiment of the present disclosure the acrylate monomer is a combination of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA) and methacrylic acid (MAA) and the amount of acrylate monomer is 36.8 mass% with respect to the total mass of the elastomeric emulsion.
The polyurethane can be at least one selected from the group consisting of an anionic aliphatic polyurethane dispersion (Bayhydrol UH 2864). In an exemplary embodiment of the present disclosure, the polyurethane is anionic aliphatic polyurethane dispersion (Bayhydrol UH 2864) and the amount of polyurethane is 3.5 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment, the amount of polyurethane is 3.86 mass% with respect to the total mass of the elastomeric emulsion.
In an exemplary embodiment of the present disclosure, the amount of styrene monomer is 16 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure, the amount of styrene monomer is 27.98 mass% with respect to the total mass of the elastomeric emulsion.
The initiator can be at least one selected from the group consisting of potassium per sulfate (PPS), ammonium persulphate and sodium persulphate. In an exemplary embodiment of the present disclosure, the initiator is potassium per sulfate (PPS) and the amount of initiator is 0.32 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure, the amount of initiator is 0.5 mass% with respect to the total mass of the elastomeric emulsion.
The buffering agent is sodium bicarbonate. In an exemplary embodiment of the present disclosure, the amount of buffering agent is 0.12 mass%. In another exemplary embodiment of the present disclosure, the amount of buffering agent is 0.5 mass%.
The surfactant can be at least one selected from the group consisting of an anionic surfactant and a nonionic surfactant.
The anionic surfactant is selected from the group consisting of sodium laureth sulfate (SLS), Alkyldiphenyloxide Disulfonate (Dowfax 2A1) and ammonium phosphate, polyoxyethylene tridecyl ether (Rhodafac rs 610 A25). In an exemplary embodiment of the present disclosure, the anionic surfactant is sodium laureth sulfate (SLS).
The nonionic surfactant can be at least one selected from the group consisting of alcohol polyglycol ethers (Spectra TY) and alcohol ethoxylate (ATPOL 5720-AS-LQ-TH, ATPOL-5731/70N). In an exemplary embodiment of the present disclosure, the nonionic surfactant is alcohol polyglycol ether (Spectra TY).
In an exemplary embodiment of the present disclosure, the amount of surfactant is 2.25 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure, the amount of surfactant is 2.5 mass% with respect to the total mass of the elastomeric emulsion.
The first additive can be at least one selected from the group consisting of tert-Butyl hydroperoxide (TBHP) and sodium formaldehydesulfoxylate (SFS). In an exemplary embodiment of the present disclosure, the first additive is a mixture of tert-Butyl hydroperoxide (TBHP) and sodium formaldehydesulfoxylate (SFS) and the amount of the first additive is 0.6 mass% with respect to the total mass of the elastomeric emulsion.
The second additive can be at least one selected from the group consisting of a preservative and a neutralizing agent.
The neutralizing agent can be at least one selected from the group consisting of ammonia, sodium hydroxide, 2-amino-2-methyl-1-propanol (AMP-95), mono ethanol amine (MEA).
The preservative can be at least one selected from the group consisting of a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX150), chlor-methyl and methyl isothiazolinone (NIPACIDE CI 15 MV), mixture of sodium nitrate, 5-chloro-2-methyl-2H-isothiazol-3one and 2-methyl-2H-isothiazol-3-one (PREVENTOL D7 LT) .
In an exemplary embodiment of the present disclosure, the second additive is a mixture of ammonia and a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX150) and the amount of second additive is 0.6 mass% with respect to the total mass of the elastomeric emulsion.
The fluid medium is water.
In accordance with the present disclosure, the emulsion is having a core shell structure.
In accordance with the present disclosure, a mass ratio of polyurethane compound to monomers in the emulsion is in the range of 1:10 to 1:30. In an exemplary embodiment of the present disclosure, the mass ratio of polyurethane compound to monomers is 1:15 (3.5:52.8).
In accordance with the present disclosure, the core and shell structure of the emulsion provides elongation and maintains the tensile strength along with resistance to water, alkali, and efflorescence.
In accordance with the present disclosure, a total solid content of the emulsion is in the range of 50 wt% to 60 wt%. In an exemplary embodiment of the present disclosure, the total solid content of the emulsion is 56.5 wt%.
In accordance with the present disclosure, the specific mass ratio of polyurethane compound to monomers (which is in the range of 1:20 to 1:30) along with specific mass% of ingredients are the key parameters to achieve the following desired properties:
• excellent water and alkali resistant properties;
• desired tensile strength and high elongation in the cementitious waterproofing membrane application; and
• excellent anti-efflorescence properties.
In a second aspect, the present disclosure provides a process for the preparation of an elastomeric emulsion. The process comprises the following steps:
a. mixing predetermined amounts of at least one surfactant, at least one polyurethane compound, at least one buffering agent in a predetermined amount of a fluid medium to obtain a first mixture.
b. heating the first mixture to a first predetermined temperature under stirring at a predetermined stirring speed for a first predetermined time period to obtain a heated first mixture;
c. separately, preparing an initiator solution by mixing a predetermined amount of at least one initiator in a predetermined amount of a fluid medium;
d. separately, preparing a pre-emulsion solution by mixing predetermined amounts of at least one acrylate monomer, at least one styrene monomer, at least one initiator and at least one surfactant in a predetermined amount of the fluid medium.
e. adding a predetermined amount of the initiator solution to the heated first mixture followed by adding a predetermined amount of the pre-emulsion solution over a second predetermined time period to obtain a second mixture;
f. adding a predetermined amount of at least one first additive while maintaining the first predetermined temperature for a third predetermined time period to obtain a third mixture;
g. cooling the third mixture to a second predetermined temperature to obtain a cooled third mixture;
h. adding a predetermined amount of at least one second additive to the cooled third mixture to obtain an emulsion; and
i. filtering the emulsion to obtain the elastomeric emulsion.
The process for the preparation of an elastomeric emulsion is described in detail herein below.
Firstly, predetermined amounts of at least one surfactant, at least one polyurethane compound, at least one buffering agent are mixed in a predetermined amount of a fluid medium to obtain a first mixture.
The surfactant can be at least one selected from the group consisting of an anionic surfactant and a nonionic surfactant.
The anionic surfactant is selected from the group consisting of sodium laureth sulfate (SLS), alkyldiphenyloxide disulfonate (Dowfax 2A1), ammonium phosphate, polyoxyethylene tridecyl ether (Rhodafac rs 610 A25). In an exemplary embodiment of the present disclosure, the anionic surfactant is sodium laureth sulfate (SLS).
The nonionic surfactant can be at least one selected from the group consisting of alcohol polyglycol ethers (Spectra TY) and alcohol ethoxylate (ATPOL 5720-AS-LQ-TH, ATPOL-5731/70N). In an exemplary embodiment of the present disclosure, the nonionic surfactant is alcohol polyglycol ethers (Spectra TY).
The surfactant is used in an amount in the range of 1 mass% to 5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the amount of surfactant is 2.25 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure, the amount of surfactant is 2.5 mass% with respect to the total mass of the elastomeric emulsion.
The polyurethane can be at least one selected from the group consisting of an anionic aliphatic polyurethane dispersion (Bayhydrol UH 2864). In an exemplary embodiment of the present disclosure, the polyurethane is anionic aliphatic polyurethane dispersion (Bayhydrol UH 2864).
The polyurethane is used in an amount in the range of 1 mass% to 5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure the amount of polyurethane is 3.5 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure the amount of polyurethane is 3.86 mass% with respect to the total mass of the elastomeric emulsion.
The buffering agent is sodium bicarbonate. The amount of buffering agent is in the range of 0.05 mass% to 1 mass% with respect to the total mass of the elastomeric emulsion. In an exemplary embodiment of the present disclosure, the amount of buffering agent is 0.12 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure, the amount of buffering agent is 0.5 mass% with respect to the total mass of the elastomeric emulsion.
The fluid media can be at least one selected from the group consisting of water. In an exemplary embodiment of the present disclosure, the fluid medium is water.
The first mixture is then heated to a first predetermined temperature under stirring at a predetermined stirring speed for a first predetermined time period to obtain a heated first mixture.
In accordance with the present disclosure, the first predetermined temperature is in the range of 70 °C to 90 °C. In an exemplary embodiment of the present disclosure, the first predetermined temperature is 80 °C.
In accordance with the present disclosure, the predetermined stirring speed is in the range of 100 rpm to 300 rpm. In an exemplary embodiment of the present disclosure, the predetermined stirring speed is 200 rpm.
In accordance with the present disclosure, the first predetermined time period is in the range of 10 minutes to 30 minutes. In an exemplary embodiment of the present disclosure, the first predetermined time period is 15 minutes.
Separately, an initiator solution is prepared by mixing a predetermined amount of at least one initiator in a predetermined amount of a fluid medium.
The initiator can be at least one selected from the group consisting of potassium per sulfate (PPS) and ammonium persulphate and sodium persulphate. In an exemplary embodiment of the present disclosure, the initiator is potassium per sulfate (PPS).
The initiator is used in an amount 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 amount of initiator is 0.32 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure the amount of initiator is 0.5 mass% with respect to the total mass of the elastomeric emulsion.
Further, separately, a pre-emulsion solution is prepared by mixing predetermined amounts of at least one acrylate monomer, at least one styrene monomer, at least one initiator and at least one surfactant in a predetermined amount of a fluid medium.
The acrylate monomer can be at least one selected from the group consisting of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA), methacrylic acid (MAA), methyl methacrylate (MMA), isobornyl acrylate, isobornyl methacrylate, cyclohexyl methacrylate, 2-ethyl hexyl acrylate (2EHA) and isobutyl acrylate. In an exemplary embodiment of the present disclosure, the acrylate monomer is a combination of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA), methacrylic acid (MAA).
The acrylate monomer is used in an amount in the range of 20 mass% to 70 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the amount of acrylate monomer is 36.8 mass% with respect to the total mass of the emulsion. In another exemplary embodiment of the present disclosure, the amount of acrylate monomer is 64.65 mass% with respect to the total mass of the emulsion.
The styrene monomer is used in an amount in the range of 5 mass% to 30 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure, the amount of styrene monomer is 16 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure, the amount of styrene monomer is 27.98 mass% with respect to the total mass of the elastomeric emulsion.
The initiator can be at least one selected from the group consisting of potassium per sulfate (PPS), ammonium persulphate and sodium persulphate. In an exemplary embodiment of the present disclosure, the initiator is potassium per sulfate (PPS).
The initiator is used in an amount 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 amount of initiator is 0.32 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure the amount of initiator is 0.5 mass% with respect to the total mass of the elastomeric emulsion.
The surfactant can be at least one selected from the group consisting of anionic surfactant and nonionic surfactant.
The anionic surfactant is selected from the group consisting of sodium laureth sulfate (SLS), alkyldiphenyloxide disulfonate (Dowfax 2A1), ammonium phosphate, polyoxyethylene tridecyl ether (Rhodafac rs 610 A25). In an exemplary embodiment of the present disclosure, the anionic surfactant is sodium laureth sulfate (SLS).
The nonionic surfactant can be at least one selected from the group consisting of alcohol polyglycol ethers (Spectra TY) and alcohol ethoxylate (ATPOL 5720-AS-LQ-TH and ATPOL-5731/70N). In an exemplary embodiment of the present disclosure, the nonionic surfactant is alcohol ethoxylate (Spectra TY).
The surfactant is used in an amount in the range of 1 mass% to 5 mass% with respect to the total mass of the emulsion. In an exemplary embodiment of the present disclosure the amount of surfactant is 2.25 mass% with respect to the total mass of the elastomeric emulsion. In another exemplary embodiment of the present disclosure the amount of surfactant is 2.5 mass% with respect to the total mass of the elastomeric emulsion.
Further, a predetermined amount of the so prepared initiator solution is added to the heated first mixture followed by the addition of a predetermined amount of the pre-emulsion solution over a second predetermined time period to obtain a second mixture.
The second predetermined time period in accordance with the present disclosure is in the range of 200 minutes to 300 minutes. In an exemplary embodiment of the present disclosure, the second predetermined time period is 240 minutes
A predetermined amount of at least one first additive is added to the second mixture while maintaining the first predetermined temperature for a third predetermined time period to obtain a third mixture.
The first additive can be at least one selected from the group consisting of tert-Butyl hydroperoxide (TBHP) and sodium formaldehydesulfoxylate (SFS). In an exemplary embodiment of the present disclosure, the first additive is a mixture of tert-Butyl hydroperoxide (TBHP) and Sodium formaldehydesulfoxylate (SFS).
The first additive is used in an amount 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 amount of the first additive is 0.6 mass% with respect to the total mass of the elastomeric emulsion.
In accordance with the present disclosure, the first predetermined temperature is in the range of 70 °C to 90 °C. In an exemplary embodiment of the present disclosure, the first predetermined temperature is 80 °C.
In accordance with the present disclosure, the third predetermined time period is in the range of 30 minutes to 70 minutes. In an exemplary embodiment of the present disclosure, the third predetermined time period is 45 minutes.
The third mixture is then cooled to a second predetermined temperature to obtain a cooled third mixture.
In accordance with the present disclosure, the second predetermined temperature is in the range of 25 °C to 35 °C. In an exemplary embodiment of the present disclosure, the second predetermined temperature is 30 °C.
A predetermined amount of at least one second additive is added to the cooled third mixture to obtain an emulsion.
The second additive can be at least one selected from the group consisting of a preservative and a neutralizing agent.
The neutralizing agent can be at least one selected from the group consisting of ammonia, sodium hydroxide, 2-amino-2-methyl-1-propanol (AMP-95), mono ethanol amine (MEA).
The preservative can be at least one selected from the group consisting of a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX150), chlor-methyl and methyl isothiazolinone (NIPACIDE CI 15 MV), mixture of sodium nitrate, 5-chloro-2-methyl-2H-isothiazol-3one and 2-methyl-2H-isothiazol-3-one (PREVENTOL D7 LT).
In an exemplary embodiment of the present disclosure, the second additive is a mixture of ammonia and a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX150).
The second additive is used in an amount 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 amount of the second additive is 0.6 mass% with respect to the total mass of the elastomeric emulsion.
The so obtained emulsion is filtered to obtain the elastomeric emulsion.
In accordance with the present disclosure, the emulsion is filtered through 80 nylon mesh.
In accordance with the present disclosure, the polyurethane along with styrene and acrylate monomers are polymerized by emulsion polymerization process.
The emulsion in accordance with the present disclosure is having a core shell structure.
In accordance with the present disclosure, the mass ratio of the polyurethane compound to monomers in the emulsion is in the range of 1:10 to 1:30. In an exemplary embodiment of the present disclosure, the mass ratio of polyurethane compound to monomers is 1:15 (3.5:52.8).
In accordance with the present disclosure, a total solid content of the emulsion is in the range of 50 wt% to 60 wt%. In an exemplary embodiment of the present disclosure, the total solid content of the emulsion is 56.5 wt%.
The present disclosure provides an elastomeric emulsion that is compatible with cement and can be used to eliminate water seepage or leakage in the buildings.
The foregoing description of the embodiments has been provided for purposes of illustration and is 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 the industrial scale.
EXPERIMENTAL DETAILS
Experiment 1: Preparation of an elastomeric emulsion in accordance with the present disclosure
Example 1: 0.05g of sodium laureth sulfate (SLS), 0.2g of alcohol polyglycol ether (Spectra TY), 3.5g of anionic aliphatic polyurethane dispersion (Bayhydrol UH2864) and 0.12g of sodium bicarbonate were mixed in a glass kettle equipped with a mechanical stirrer, reflux condenser, thermometer and inlet tube for pre emulsion feeding to obtain a first mixture. The first mixture was heated gradually to 80°C under stirring at 200 rpm for 15 minutes to obtain a heated first mixture.
Separately, 0.12g of potassium per sulfate (PPS) was mixed in 2g of water to obtain a potassium per sulfate solution (Initiator solution).
Separately, 34g of butyl acrylate, 2g of hydroxyl ethyl methacrylate and 0.8 g of methacrylic acid, 16 g of styrene, 0.2g of potassium per sulfate (PPS), 0.5g of sodium lauryl ether sulfate (SLS) and 1.5g of alcohol polyglycol ether (Spectra TY) were mixed in 18g of water to obtain a pre-emulsion solution.
Separately prepared potassium per sulfate (PPS) solution was added to the obtained heated first mixture followed by the slow addition of the pre-emulsion solution (prepared separately) over 240 minutes to obtain a second mixture.
Separately TBHP solution and SFS solution were prepared:
0.3g of tert-Butyl hydroperoxide (TBHP) was dissolved in 1ml of water to obtain a TBHP solution. 0.3g (0.3 mass %) of sodium formaldehydesulfoxylate (SFS) was dissolved in 1ml of water to obtain a Sodium formaldehydesulfoxylate (SFS) solution.
TBHP solution and SFS solution were added separately to the second mixture while maintaining the temperature at 80 °C for 45 minutes to obtain a third mixture. The third mixture was cooled to 30°C to obtain a cooled third mixture.
0.4g of ammonia (21%) was dissolved in 2ml of water to obtain an ammonia solution. 0.2g of Kathon LX 150 was dissolved in 2ml of water to obtain Kathon LX 150 solution.
Ammonia solution and Kathon LX 150 solution were added to the cooled third mixture to obtain an emulsion. The resulting emulsion was filtered through 80 nylon mesh to obtain an elastomeric emulsion.
Comparative example: An emulsion was prepared by following the same procedure of example 1 without using the polyurethane dispersion.
Experiment 2: Properties of elastomeric emulsion
A. The elastomeric emulsions prepared in example 1 and comparative example 1 were tested to determine the various properties. The results are summarized in Table 1.
Table 1: Properties of elastomeric emulsion prepared in accordance with the present disclosure and elastomeric emulsions of comparative example 1
Sr. No. Properties Example 1 Elastomeric emulsions of comparative example 1
1. pH 6 6
2. % Non volatile material (NVM) 56.6 54.6
3. Viscosity [gms] 80 74
4. Particle size (nm) 200 195
5. Mechanical stability Stable Stable
6. Accelerated stability (@ 50?C,15 days) Initial viscosity & final viscosity pass pass
7. Electrolytic stability ml/100 g 40 30

8. % Elongation at Break of emulsion 3620 1320
9. Tensile strength (MPa) of emulsion 0.310 0.568
In the elastomeric emulsion of example 1, prepared in accordance with the present disclosure, the polyurethane dispersion core provides the desired elongation at break to the elastomeric emulsion. When the elongation at break is higher, the tensile strength of the elastomeric emulsion will be low. In the elastomeric emulsion of comparative example 1 polyurethane dispersion core is absent and hence the tensile strength of elastomeric emulsion is high.
The elastomeric emulsion of example 1, prepared in accordance with the present disclosure was found to be 3 times more stretchable than elastomeric emulsion of the comparative example.
B. Determination of tensile strength and elongation of the substrate coated with the elastomeric emulsions prepared in example 1 in accordance with the present disclosure and comparative example 1.
50ml of elastomeric emulsions prepared in example 1 and comparative example were separately mixed with 100g of cement powder to obtain two different mixtures. Two different panels were prepared by applying the two different mixtures on two different substrates. The substrates were cured for 14 days to obtain cured panels. The cured panels were subjected for tensile strength and % elongation measurements. The results are summarized in Table 2.
Table 2: Tensile strength and % elongation of the substrates coated with elastomeric emulsions prepared in example 1 in accordance with the present disclosure and comparative example.

Sr. No. Properties Substrate coated with elastomeric emulsion of example 1 Substrate coated with elastomeric emulsions of comparative example 1
1. Tensile strength 0.73 MPa 0.7 MPa
2. % Elongation 106 70

The elastomeric emulsion prepared in accordance with the present disclosure has high elongation (i.e. more than 100%) whereas the emulsion of the comparative example has elongation below 100%. The property of high elongation is achieved due to the polyurethane compound in the elastomeric emulsion of the present disclosure.
C. Study of water resistance of substrates coated with elastomeric emulsions prepared in example 1 and comparative example.
The two panels prepared in Experiment 2 (B) were subjected to the water resistance mesurements after 21 days of exposure to moisture. The results are summarized in Table 3.
Table 3: Water resistance of substrates applied with elastomeric emulsions of example 1 and comparative example
Sr. No. Properties Substrate coated with elastomeric emulsion of Example 1 Substrate coated with elastomeric emulsions of comparative example
1. Water resistance 8-10% moisture on surface 15-20% moisture on surface
D. Study of efflorescence resistance of substrates coated with elastomeric emulsions of example 1 and comparative example
The elastomeric emulsions prepared in example 1 and comparative example were applied on two different substrates. Both the substrates were dipped in a salt solution for 21 days and observed the efflorescence on the surface of substrates after 21 days.
Sr. No. Properties Substrate with elastomeric emulsion prepared in accordance with the present disclosure Substrate coated with elastomeric emulsions of comparative example
1. Efflorescence resistance No efflorescence Efflorescence observed
TECHNICAL ADVANCEMENTS
The present disclosure described hereinabove has several technical advantages including, but not limited to, the realization of an elastomeric emulsion that:
• has excellent water and alkali resistant properties;
• achieves desirable tensile strength and high elongation in the cementitious waterproofing membrane application; and
• has excellent anti-efflorescence properties; and
• shows 100% or more than 100% elongation when mixed with cement even after 14 days of curing.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
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.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
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. , Claims:WE CLAIM:
1. An elastomeric emulsion being a reaction product of:
i. monomers selected from at least one styrene monomer and at least one acrylate monomer;
ii. a polyurethane compound;
iii. at least one initiator;
iv. at least one buffering agent;
v. at least one surfactant;
vi. at least one first additive;
vii. at least one second additive; and
viii. a fluid medium.
2. The emulsion as claimed in claim 1, wherein
i. said styrene monomer is in an amount in the range of 5 mass% to 30 mass%;
ii. said acrylate monomer is in an amount in the range of 20 mass% to 70 mass%;

iii. said polyurethane compound is in an amount in the range of 1 mass% to 5 mass%;
iv. said initiator is in an amount in the range of 0.1 mass% to 1 mass%;
v. said buffering agent is in an amount in the range of 0.05 mass% to 1 mass%;
vi. said surfactant is in an amount in the range of 1 mass% to 5 mass%;
vii. said first additive is in an amount in the range of 0.1 mass% to 1 mass%;
viii. said second additive is in an amount in the range of 0.1 mass% to 1 mass%; and
ix. q.s. said fluid medium,
wherein mass% of each component is with respect to the total mass of said emulsion.
3. The emulsion as claimed in claim 1, wherein
i. said styrene monomer is in an amount in the range of 10 mass% to 30 mass%;
ii. said acrylate monomer is in an amount in the range of 30 mass% to 70 mass%;
iii. said polyurethane compound is in an amount in the range of 3 mass% to 4 mass%;
iv. said initiator is in an amount in the range of 0.2 mass% to 0.8 mass%;
v. said buffering agent is in an amount in the range of 0.1 mass% to 0.8 mass%;
vi. said surfactant is in an amount in the range of 2 mass% to 3 mass%;
vii. said first additive is in an amount in the range of 0.4 mass% to 0.8 mass%; and
viii. said second additive is in an amount in the range of 0.4 mass% to 0.8 mass%; and
ix. said fluid medium is in an amount in the range of 10 mass% to 50 mass%,
wherein mass% of each component is with respect to the total mass of said emulsion.
4. The emulsion as claimed in claim 1, wherein said polyurethane compound is an anionic aliphatic polyurethane dispersion and said acrylate monomer is at least one selected from the group consisting of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA), methacrylic acid (MAA), methyl methacrylate (MMA), isobornyl acrylate, isobornyl methacrylate, cyclohexyl methacrylate, 2-ethyl hexyl acrylate (2EHA) and isobutyl acrylate.
5. The emulsion as claimed in claim 1, wherein said initiator is at least one selected from the group consisting of potassium per sulfate (PPS), ammonium persulphate and sodium persulphate.
6. The emulsion as claimed in claim 1, wherein said buffering agent is sodium bicarbonate; and wherein said fluid medium is water.
7. The emulsion as claimed in claim 1, wherein said surfactant is selected the group consisting of an anionic surfactant and a nonionic surfactant.
8. The emulsion as claimed in claim 7, wherein said anionic surfactant is at least one selected from the group consisting of sodium laureth sulfate (SLS), alkyldiphenyloxide disulfonate and ammonium phosphate, polyoxyethylene tridecyl ether.
9. The emulsion composition as claimed in claim 7, wherein said nonionic surfactant is at least one selected from the group consisting of alcohol polyglycol ethers and alcohol ethoxylate.
10. The emulsion as claimed in claim 1, wherein said first additive is at least one selected from the group consisting of tert-Butyl hydroperoxide (TBHP) and Sodium formaldehydesulfoxylate (SFS).
11. The emulsion as claimed in claim 1, wherein said second additive is at least one selected from the group consisting of a preservative and a neutralizing agent.
12. The emulsion as claimed in claim 11, wherein said preservative is selected from a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, a mixture of chlor-methyl and methyl isothiazolinone and a mixture of sodium nitrate, 5-chloro-2-methyl-2H-isothiazol-3one and 2-methyl-2H-isothiazol-3-one and said neutralizing agent is at least one selected from the group consisting of ammonia, sodium hydroxide, 2-amino-2-methyl-1-propanol (AMP), Mono ethanol amine (MEA).
13. The emulsion as claimed in claim 1, wherein said emulsion is having a core-shell structure.
14. The emulsion as claimed in claim 1, wherein a mass ratio of said polyurethane compound to said monomers is in the range of 1:10 to 1:30.
15. The emulsion as claimed in claim 1, wherein a total solid content of said emulsion is in the range of 50 wt% to 60 wt%.
16. A process for the preparation of an elastomeric emulsion, said process comprising the following steps:
a. mixing predetermined amounts of at least one surfactant, at least one polyurethane compound, at least one buffering agent in a predetermined amount of a fluid medium to obtain a first mixture;
b. heating said first mixture to a first predetermined temperature under stirring at a predetermined stirring speed for a first predetermined time period to obtain a heated first mixture;
c. separately, preparing an initiator solution by mixing a predetermined amount of at least one initiator in a predetermined amount of a fluid medium;
d. separately, preparing a pre-emulsion solution by mixing predetermined amounts of at least one acrylate monomer, at least one styrene monomer, at least one initiator and at least one said surfactant in a predetermined amount of said fluid medium;
e. adding a predetermined amount of said initiator solution to said heated first mixture followed by adding a predetermined amount of said pre-emulsion solution over a second predetermined time period to obtain a second mixture;
f. adding a predetermined amount of at least one first additive while maintaining said first predetermined temperature for a third predetermined time period to obtain a third mixture;
g. cooling said third mixture to a second predetermined temperature to obtain a cooled third mixture;
h. adding a predetermined amount of at least one second additive to said cooled third mixture to obtain an emulsion; and
i. filtering said emulsion to obtain said elastomeric emulsion.
17. The process as claimed in claim 16, wherein said surfactant is selected from an anionic surfactant and a nonionic surfactant; and wherein said predetermined amount of said surfactant is in the range of 1 mass% to 5 mass% with respect to the total mass of said elastomeric emulsion.
18. The process as claimed in claim 17, wherein said anionic surfactant is at least one selected from sodium laureth sulfate (SLES), alkyldiphenyloxide disulfonate and ammonium phosphate, polyoxyethylene tridecyl ether;
19. The process as claimed in claim 17, wherein said nonionic surfactant is at least one selected from the group consisting of alcohol polyglycol ethers and alcohol ethoxylate.
20. The process as claimed in claim 16, wherein said polyurethane compound is an anionic aliphatic polyurethane dispersion; and wherein said predetermined amount of said polyurethane is in the range of 1 mass% to 5 mass% with respect to the total mass of said emulsion.
21. The process as claimed in claim 16, wherein said buffering agent is sodium bicarbonate; and wherein said predetermined amount of said buffering agent is in the range of 0.05 mass% to 1 mass% with respect to the total mass of said emulsion.
22. The process as claimed in claim 16, wherein said fluid medium is water; and wherein said predetermined amount of said fluid medium is in the range of 10 mass% to 50 mass% with respect to the total mass of said emulsion.
23. The process as claimed in claim 16, wherein said first predetermined temperature is in the range of 70°C to 90°C;
24. The process as claimed in claim 16, wherein said second predetermined temperature is in the range of 25°C to 35°C.
25. The process as claimed in claim 16, wherein said predetermined stirring speed is in the range of 100rpm to 300rpm.
26. The process as claimed in claim 16, wherein said initiator is at least one selected from the group consisting of potassium per sulfate (PPS),ammonium persulphate and Sodium persulphate ; and wherein said predetermined amount of initiator is in the range of 0.1 mass% to 1 mass%.
27. The process as claimed in claim 16, wherein said acrylate monomer is at least one selected from the group consisting of hydroxy ethyl methacrylate (HEMA), butyl acrylate (BA), methacrylic acid (MAA), methyl methacrylate (MMA), isobornyl acrylate, isobornyl methacrylate, cyclohexyl methacrylate, 2-ethyl hexyl acrylate (2EHA) and isobutyl acrylate and wherein said predetermined amount of said acrylate monomer is in the range of 20 mass% to 70 mass% with respect to the total mass of said emulsion.
28. The process as claimed in claim 16, wherein said predetermined amount of said styrene monomer is in the range of 5 mass% to 30 mass% with respect to the total mass of said emulsion.
29. The process as claimed in claim 16, wherein said first predetermined time period is in the range of 10 minutes to 30 minutes; said second predetermined time period is in the range of 200 minutes to 300 minutes; and said third predetermined time period is in the range of 30 minutes to 70 minutes.
30. The process as claimed in claim 16, wherein said first additive is at least one selected from the group consisting of tert-Butyl hydroperoxide (TBHP) and Sodium formaldehydesulfoxylate (SFS); and wherein said predetermined amount of first additive is in the range of 0.1 mass% to 1 mass% with respect to the total mass of said emulsion.
31. The process as claimed in claim 16, wherein said second additive is at least one selected from the group consisting of at least one preservative and at least one neutralizing agent; and said predetermined amount of said second additive is in the range of 0.1 mass% to 1 mass% with respect to the total mass of said emulsion.
32. The process as claimed in claim 31, wherein said neutralizing agent is at least one selected from the group consisting of ammonia, sodium hydroxide, 2-amino-2-methyl-1-propanol (AMP), Mono ethanol amine (MEA) and said preservative is at least one selected from the group consisting of a mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, a mixture of Chlor-methyl and methyl isothiazolinone and a mixture of sodium nitrate, 5-chloro-2-methyl-2H-isothiazol-3one and 2-methyl-2H-isothiazol-3-one;
33. The process as claimed in claim 16, wherein said emulsion is having a core-shell structure.
34. The process as claimed in claim 16, wherein a mass ratio of said polyurethane compound to said monomers is in the range of 1:10 to 1:30.
35. The process as claimed in claim 16, wherein a total solid content of said emulsion is in the range of 50wt% to 60wt%.

Dated this 07th day of July, 2023

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K.DEWAN & CO.
Authorized Agent of Applicant

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI