DESC:FIELD
The present disclosure relates to a copolymer composition 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.
Lap-shear strength refers to the ability of an adhesive to resist forces in the plane of the bonded surfaces.
D3 performance refers to the ability of an adhesive to resist frequent short-term exposure to running or condensed water and/or to heavy exposure to high humidity in interior applications. European Standard classifies thermoplastic resin based wood adhesives for non-structural applications into durability classes D3 as per standard EN 204 that adhesive must provide minimum values of 2 N/mm2 adhesive strength for thin bond-lines on wood substrate after 7 days exposure in standard atmosphere followed by 4 days exposure in cold water at (20 ±5)°C.
Boiling water resistance refers to the ability of an adhesive to resist minimum 6 hours exposure in boiling water means wood panel must not detached after 6 hour exposure.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Conventional vinyl based homopolymers or copolymers have poor balance between the properties such as elongation, tensile strength and lap shear strength with inferior water resistance. Further, the conventional vinyl based homopolymers or copolymers system with better water resistance are prepared via pre or post crosslinking route.
Typically, the high water-resistant vinyl based homopolymers or copolymers are prepared by inserting a self-crosslinking comonomer. Examples of such self-crosslinking comonomer are N-methylolacrylamide, (meth)acrylamide, diallyl phthalate, diallyl maleate, triallyl cyanurate, tetraallyloxyethane, divinylbenzene, butane-1,4-diol dimethacrylate, triethylene glycol dimethacrylate, divinyl adipate, allyl (meth)acrylate, vinyl crotonate, methylenebisacrylamide, hexanediol diacrylate, pentaerythritol diacrylate and trimethylolpropane triacrylate and/or mixtures of two or more compounds. Further, the high water-resistant vinyl based homopolymers or copolymers can also be prepared by using either organic crosslinkers such as glyoxal, glutaraldehyde, citric acid, tartaric acid and the like and/or inorganic crosslinkers such as acidic metal salts such as A1C13, AlNO3, Borates and the like. The organic crosslinkers can also be used in combination with the self-crosslinking comonomers. However, due to the addition of the self-crosslinking monomers and organic cross-linkers, the shelf life (stability) of the copolymer system reduces significantly as a result of the continuous viscosity build up over the time.
Therefore, there is felt a need to provide a copolymer composition that can mitigate the drawbacks mentioned herein above.
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 a copolymer composition.
Still another object of the present disclosure is to provide a copolymer composition comprising capped polyurethane grafted with vinyl polymer or acrylic-vinyl polymer.
Yet another object of the present disclosure is to provide a copolymer composition comprising capped polyurethane grafted with vinyl polymer.
Still another object of the present disclosure is to provide a copolymer composition comprising capped polyurethane grafted with acrylic-vinyl polymer.
Yet another object of the present disclosure is to provide a copolymer composition that can provide excellent water resistance, longer shelf life, faster handling strength and increased mechanical properties.
Still another object of the present disclosure is to provide a process for the preparation of a copolymer composition.
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 a copolymer composition comprising a capped polyurethane, one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer, a polyvinyl alcohol, a defoamer, a buffer, a stabilizer, an initiator and a fluid medium; wherein the capped polyurethane is in-situ grafted with the polymer.
The present disclosure further relates to a process for the preparation of a copolymer composition. The process comprises the step of obtaining a capped polyurethane. Separately, a polyvinyl alcohol is dissolved in a fluid medium in a reactor at a first predetermined temperature under stirring for a first predetermined time period to obtain a first mixture. Separately, a predetermined amount of at least one monomer is mixed with a predetermined amount of the capped polyurethane to obtain a second mixture. A first buffer solution and a first predetermined amount of the second mixture are added to the first mixture, followed by adding a first predetermined amount of an initiator at a second predetermined temperature and stirring for a second predetermined time period to obtain a third mixture. A second predetermined amount of the second mixture and a second predetermined amount of at least one initiator are gradually added to the third mixture over a third predetermined time period and reacting in the presence of a chaser catalyst at a third predetermined temperature to obtain a slurry. The predetermined amounts of a stabilizer, a defomer and a second buffer solution are added to the slurry at a fourth predetermined temperature under stirring for a fourth predetermined time period to obtain the copolymer composition.
DETAILED DESCRIPTION
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.
Conventional vinyl based homopolymer or copolymer has a poor balance between the properties such as elongation, tensile strength and lap shear strength with inferior water resistance. Further, the conventional vinyl based homopolymer or copolymer system with better water resistance is prepared via pre or post crosslinking route. However, due to the pre or post addition of cross-linkers, the shelf life of the copolymer system reduces significantly due to the continuous viscosity pick up with time. Hence, there is a need for vinyl based or vinyl-acrylic based copolymer which will give balance between the properties such as lap shear strength, excellent water resistance and excellent durability of D3 class with shelf life more than twelve months and also without the use of any additional crosslinkers.
The present disclosure provides a copolymer composition and a process for its preparation.
In a first aspect, the present disclosure provides a copolymer composition comprising;
a. a capped polyurethane;
b. one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c. a polyvinyl alcohol polymer;
d. a defoamer;
e. a buffer;
f. a stabilizer;
g. an initiator; and
h. a fluid medium; and
wherein the capped polyurethane is in-situ grafted with the polymer.
In accordance with the present disclosure, at least one end of the polyurethane is capped with a capping agent. In an embodiment, only one end of the polyurethane is capped. In another embodiment, both the ends of the polyurethane are capped.
In accordance with the embodiments of the present disclosure, the capping agent has at least one functionality selected from hydroxyl-acrylate, epoxy, silane and alcohol.
In accordance with the present disclosure, the capping agent having hydroxyl-acrylate functionality is selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, N-hydroxyethyl acrylamide, N-(2-hydroxypropyl)methacrylamide, 3-phenoxy-2-hydroxypropyl methacrylate, glycerol methacrylate and polyethyleneglycol monomethacrylate.
In an exemplary embodiment of the present disclosure, the capping agent having hydroxyl-acrylate functionality is hydroxypropyl acrylate. In another exemplary embodiment of the present disclosure, the capping agent having hydroxyl-acrylate functionality is hydroxyethyl methacrylate. In yet another exemplary embodiment of the present disclosure, the capping agent having hydroxyl-acrylate functionality is polyethyleneglycol monomethacrylate. In still another exemplary embodiment of the present disclosure, the capping agent having hydroxyl-acrylate functionality is N-hydroxyethyl acrylamide. In yet another exemplary embodiment of the present disclosure, the capping agent having hydroxyl-acrylate functionality is N-(2-hydroxypropyl)methacrylamide.
In accordance with the present disclosure, the capping agent having epoxy functionality is selected from diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E and diglycidyl ether of bisphenol-S.
In accordance with the present disclosure, the capping agent having silane functionality is selected from amino silanes; wherein the amino silanes are selected from 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-methyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-triethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride.
In accordance with the present disclosure, the capping agent having alcohol functionality is selected from isopropyl alcohol, isobutyl alcohol, isoctyl alcohol and benzyl alcohol. In an exemplary embodiment of the present disclosure, the capping agent having alcohol functionality is isopropyl alcohol. In another exemplary embodiment of the present disclosure, the capping agent having alcohol functionality is isobutyl alcohol. In yet another exemplary embodiment of the present disclosure, the capping agent having alcohol functionality is isoctyl alcohol. In still another exemplary embodiment of the present disclosure, the capping agent having alcohol functionality is benzyl alcohol.
In an embodiment of the present disclosure, the capped polyurethane has one end capped with a capping agent having the acrylate functionality and other end capped with a capping agent having the alcohol functionality.
In another embodiment of the present disclosure, the capped polyurethane has both the ends capped with a capping agent having the acrylate functionality.
In yet another embodiment of the present disclosure, the capped polyurethane has one end capped with a capping agent having the acrylate functionality and other end capped with a capping agent having the epoxy functionality.
In still another embodiment of the present disclosure, the capped polyurethane has one end capped with a capping agent having the acrylate functionality and other end capped with a capping agent having the silane functionality.
In accordance with the present disclosure, the molecular weight of the capped polyurethane is in the range of 1000 g/mol to 5000 g/mol.
The molecular weight of the capped polyurethane less than 1000 g/mol, is not desirable as the required performance cannot be achieved from the low molecular weight capped polyurethane. When the Capped polyurethane having the molecular weight more than 5000g/mol is used, in-situ grafting with vinyl monomer becomes very difficult due to sudden increase in viscosity. The sudden increase in viscosity may be due to the formation of very high molecular weight copolymers in the composition. The required viscosity and performance of the copolymer composition is achieved, only when capped polyurethane having the molecular weight in the range of 1000 g/mol to 5000 g/mol is used.
In accordance with the embodiments of the present disclosure, a backbone of the capped polyurethane is modified by a modifier selected from epoxy functionality component, siloxane functionality component and a combination thereof.
In accordance with the embodiments of the present disclosure, the epoxy functionality component is selected from diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E and diglycidyl ether of bisphenol-S.
In accordance the embodiments of the present disclosure, the siloxane functionality component is selected from silanol functional phenyl-propyl polysiloxane (Silres SY 300), silanol functional phenyl polysiloxane, silanol functional methyl polysiloxane, dihydroxypolydimethylsiloxane, dihydroxypolydiethylsiloxane and amino silane compounds.
In accordance with the present disclosure, the acrylic polymer is prepared from at least one acrylic monomer selected from, methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, 2-ethyl hexyl acrylate and a combination thereof.
In accordance with the present disclosure, the vinyl polymer is prepared from at least one vinyl monomer selected from vinyl acetate, vinyl decanoate, vinyl trimethoxy silane and combination thereof.
In accordance with the present disclosure, the molecular weight of the vinyl polymer or the vinyl-acrylic polymer is in the range of 1,00,000 g/mol to 3,00,000 g/mol.
The use of vinyl polymer or the vinyl-acrylic polymer having a molecular weight less than 1,00,000 g/mol is not desirable to obtain the copolymer composition with desired properties. On the other hand, the use of vinyl polymer or the vinyl-acrylic polymer having the molecular weight more than 3,00,000 g/mol, leads to the copolymer composition having a very high viscosity.
The molecular weight of the vinyl polymer or the vinyl-acrylic polymer is dependent on the targeted properties of the composition based on their application.
In accordance with the present disclosure, the vinyl polymer or the vinyl-acrylic polymer is grafted with the capped polyurethane.
In accordance with the present disclosure, a mass ratio of the capped polyurethane to the vinyl polymer or the vinyl-acrylic polymer is in the range of 1:49 to 5:45.
In accordance with the present disclosure, the copolymer composition is stabilized by using a stabilizer.
In accordance with the present disclosure, the stabilizer is selected from sodium, potassium, or ammonium salts of fatty acids; C12 - C16 alkyl sulfates selected from sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS); nonionic stabilizers selected from poly (ethylene oxide) or hydroxyethyl cellulose, polyvinyl alcohol and a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150).
In accordance with the present disclosure, the defoamer is selected from polysiloxne containing polyglycol (BYK 022, BYK 024), polyether siloxane copolymer (Tegofoamax) and organo-silicon polymers (Foamstar ED, Foamstar ST).
In accordance with the present disclosure, the buffer is selected from ammonia buffer, sodium bicarbonate buffer and sodium acetate buffer.
In accordance with the present disclosure, the initiator is selected from ammonium persulfate, potassium persulfate, sodium persulfate and sodium metabisulfite.
In accordance with the present disclosure, the fluid medium is selected from organic solvent, water and a combination thereof.
In an embodiment of the present disclosure, the organic solvent is selected from 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-octanol and benzyl alcohol.
In accordance with the present disclosure, the polyurethane grafted vinyl copolymer or vinyl-acrylic copolymer composition has a viscosity lower than non-grafted vinyl copolymer or vinyl-acrylic copolymer by 30 to 40 poise.
The lower viscosity of the copolymer composition of the present disclosure, helps in maintaining the stability of the paint comprising the copolymer composition in terms of viscosity, which enables easy application of the paint on a substrate and also increases the shelf life of the copolymer composition as well as the shelf life of the paint comprising the copolymer composition.
In an embodiment of the present disclosure, the copolymer composition comprises:
a) a capped polyurethane having at least one end capped with a capping agent having an acrylate functionality;
b) one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c) a polyvinyl alcohol polymer;
d) a defoamer;
e) a buffer;
f) a stabilizer;
g) an initiator; and
h) a fluid medium;
wherein the capped polyurethane is in-situ grafted with the polymer.
In another embodiment of the present disclosure, the copolymer composition comprises:
a) a capped polyurethane having at least one end capped with a capping agent having an acrylate functionality and the backbone of the capped polyurethane is modified by using the component having siloxane functionality; and
b) one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c) a Polyvinyl alcohol polymer;
d) a defoamer;
e) a buffer;
f) a stabilizer;
g) an initiator; and
h) a fluid medium;
wherein the capped polyurethane is in-situ grafted with the polymer.
In yet another embodiment of the present disclosure, the copolymer composition comprises:
a) a capped polyurethane having at least one end capped with a capping agent having an acrylate functionality and the backbone of the capped polyurethane is modified by the component having epoxy functionality;
b) one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c) a polyvinyl alcohol polymer;
d) a defoamer;
e) a buffer;
f) a stabilizer;
g) an initiator; and
h) a fluid medium;
wherein the capped polyurethane is in-situ grafted with the polymer.
In still another embodiment of the present disclosure, the copolymer composition comprises:
a) a capped polyurethane having at least one end capped with a capping agent having an acrylate functionality and the backbone of the capped polyurethane is modified by a combination of the component having siloxane functionality and the component having epoxy functionality;
b) one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c) a polyvinyl alcohol polymer;
d) a defoamer;
e) a buffer;
f) a stabilizer;
g) an initiator; and
h) a fluid medium;
wherein the capped polyurethane is in-situ grafted with the polymer.
In yet another embodiment of the present disclosure, the copolymer composition comprises:
a) a capped polyurethane having one end capped by the capping agent having acrylate functionality and another end capped by an amino silane and wherein the backbone of the capped polyurethane is modified by using siloxane;
b) one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c) a polyvinyl alcohol polymer;
d) a defoamer;
e) a buffer;
f) a stabilizer;
g) an initiator; and
h) a fluid medium;
wherein the capped polyurethane is in-situ grafted with the polymer.
The copolymer composition of the present disclosure has the following characteristics:
- excellent cold water and boiling water resistance;
- faster handling strength;
- increased mechanical properties such as lap shear, tensile strength;
- balance in properties such as elongation and tensile strength with excellent water resistance;
- stable viscosity and shelf life of more than twelve months;
- circumvents the use of any additional cross-linkers; and
- useful as a binder in adhesive, coatings and sealants.
In a second aspect, the present disclosure provides a process for the preparation of a copolymer composition.
The process comprises the following step:
i. obtaining a capped polyurethane;
ii. separately, dissolving polyvinyl alcohol in a fluid medium in a reactor at a first predetermined temperature under stirring for a first predetermined time period to obtain a first mixture;
iii. separately, mixing a predetermined amount of at least one monomer with a predetermined amount of said capped polyurethane to obtain a second mixture;
iv. adding a first buffer solution and a first predetermined amount of the second mixture to the first mixture, followed by adding a first predetermined amount of at least one initiator at a second predetermined temperature and stirring for a second predetermined time period to obtain a third mixture;
v. gradually adding a second predetermined amount of the second mixture and a second predetermined amount of at least one initiator to the third mixture over a third predetermined time period and reacting in the presence of a chaser catalyst at a third predetermined temperature to obtain a slurry; and
vi. adding predetermined amounts of a stabilizer, a defomer and a second buffer solution to the slurry at a fourth predetermined temperature under stirring for a fourth predetermined time period to obtain the copolymer composition.
The process for the preparation of the copolymer composition is described in detail herein below:
Step-i: A capped polyurethane is obtained.
In accordance with the embodiment of the present disclosure, the capped polyurethane is obtained by mixing and reacting a predetermined amount of a polyol with a predetermined amount of an diisocyanate monomer in a predetermined ratio, in the presence of a predetermined amount of a water compatible hydroxyl terminated solvent, a predetermined amount of a capping agent, optionally, a predetermined amount of a modifier and optionally a predetermined amount of a catalyst, at a temperature in a range of 50 to 100 oC to obtain the capped polyurethane.
In accordance with the embodiments of the present disclosure, the polyol is selected from polyether polyol, polycarbonate polyol, polyester polyol, poly(tetramethylene ether) glycol and a combination thereof. The predetermined amount of polyol is in the range of 50 mass% to 70 mass% with respect to the mass of the capped polyurethane.
In accordance with the present disclosure, the diisocyanate monomer is selected from an isophorone diisocyanate, hexamethylene diisocyanate, hydrogenated toluene diisocyanate, toluene diisocyanate, hydrogenated diphenylmethane diisocyanate and diphenylmethane diisocyanate. The predetermined amount of the diisocyanate monomer is in the range of 15 mass% to 25 mass% with respect to the total mass of the capped polyurethane.
In accordance with the present disclosure, the predetermined ratio of the polyol to the diisocyanate is in the range of 1:1.2 to 1: 2.2.
In accordance with the present disclosure, the capping agent is selected from diisocyanatehydroxyethyl acrylate, hydroxylpropyl acrylate, hydroxylbutyl acrylate, hydroxylethyl methacrylate, hydroxylpropyl methacrylate, hydroxylbutyl methacrylate, N-hydroxyethyl acrylamide, N-(2-Hydroxypropyl)methacrylamide, 3-phenoxy-2-hydroxypropyl methacrylate, glycerol methacrylate, polyethyleneglycol monomethacrylate, diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E, diglycidyl ether of bisphenol-S, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-methyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-triethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, isopropyl alcohol, isobutyl alcohol, iso-octyl alcohol and benzyl alcohol.
The predetermined amount of the capping agent is in the range of 2 mass% to 7 mass% with respect to the mass of the capped polyurethane.
In accordance with the embodiments of the present disclosure, the modifier is selected from diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E, diglycidyl ether of bisphenol-S, silanol functional phenyl-propyl polysiloxane (Silres SY 300), silanol functional phenyl polysiloxane, silanol functional methyl polysiloxane, dihydroxypolydimethylsiloxane, dihydroxypolydiethylsiloxane and amino silane compounds.
In accordance with the embodiments of the present disclosure, the water compatible hydroxyl terminated solvent is alcohol and the predetermined amount of water compatible hydroxyl terminated solvent is in the range of 3 mass% to 8 mass% with respect to the total mass of the capped polyurethane.
In accordance with the embodiments of the present disclosure, the catalyst is selected from dibutyl tin dilaurate, dibutyltin diacetate, dimethyltin dioleate, dibutyltin dimaleate and dioctyltin dilaurate and the predetermined amount of the catalyst is in the range of 0.01 mass% to 0.1 mass% with respect to the mass of the capped polyurethane.
Step-ii: Separately, polyvinyl alcohol is dissolved in a fluid medium in a reactor at a first predetermined temperature under stirring for a first predetermined time period to obtain a first mixture.
In accordance with the present disclosure, the fluid medium is selected from organic solvent, water and a combination thereof. In an embodiment of the present disclosure, the organic solvent is selected from 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-octanol and benzyl alcohol. The predetermined amount of the fluid medium is in the range of 1 mass% to 6 mass%.
In accordance with the present disclosure, the first predetermined temperature is in the range of 70 °C to 100 °C and the first predetermined time period is in the range of 4 hours to 7 hours.
Step-iii: Separately, a predetermined amount of at least one monomer is mixed with a predetermined amount of the capped polyurethane to obtain a second mixture.
In accordance with the present disclosure, the monomer is selected from vinyl monomers and acrylic monomers and the predetermined amount of the monomer is in the range of 40 mass% to 47 mass%.
The vinyl monomer is selected from vinyl acetate, vinyl decanoate, vinyl trimethoxy silane and a combination thereof.
The acrylic monomer is selected from methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, 2-ethyl hexyl acrylate and a combination thereof.
Step-iv: A first buffer solution and a first predetermined amount of the second mixture is added to the first mixture, followed by adding a first predetermined amount of an initiator at a second predetermined temperature and stirring for a second predetermined time period to obtain a third mixture.
The initiator is selected from ammonium persulfate, potassium persulfate, sodium persulfate and sodium metabisulfite. The predetermined amount of the initiator is in the range of 0.05 mass% to 0.3 mass%.
The second predetermined temperature is in the range of 50 °C to 70 °C and the second predetermined time period is in the range of 10 minutes to 30 minutes.
Step-v: A second predetermined amount of the second mixture and a second predetermined amount of at least one initiator are gradually added to the third mixture over a third predetermined time period and reacting in the presence of a chaser catalyst at a third predetermined temperature to obtain a slurry.
The chaser catalyst is selected from ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide and tert-Butyl hydroperoxide. The predetermined amount of the chaser catalyst is in the range of 0.025 mass% to 0.05 mass%.
The third predetermined temperature is in the range of 50 °C to 70 °C and the third predetermined time period is in the range of 4 hours to 8 hours.
Step-vi: The predetermined amounts of a stabilizer, a defomer and a second buffer solution are added to the slurry at a fourth predetermined temperature under stirring for a fourth predetermined time period to obtain the copolymer composition.
In accordance with the present disclosure, the stabilizer is selected from sodium, potassium, or ammonium salts of fatty acids, C12 - C16 alkyl sulfates selected from sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS), nonionic stabilizers selected from poly (ethylene oxide) or hydroxyethyl cellulose, polyvinyl alcohol and a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150).
The first buffer is selected from sodium bicarbonate buffer and sodium acetate buffer. The second buffer is selected from ammonia buffer, sodium bicarbonate buffer and sodium acetate buffer.
In accordance with the present disclosure, the defoamer is selected from polysiloxne containing polyglycol (BYK 022, BYK 024), polyether siloxane copolymer (Tegofoamax) and organo-silicon polymers (Foamstar ED, Foamstar ST).
The fourth predetermined temperature is in the range of 25 °C to 45 °C and the fourth predetermined time period is in the range of 10 minutes to 30 minutes.
In an embodiment of the present disclosure, the copolymer composition comprises:
a) vinyl acetate (vinyl monomer) in an amount in the range of 40 to 60 mass% with respect to the total mass of the composition;
b) polyvinyl alcohol in an amount in the range of 2 to 6 mass% with respect to the total mass of the composition;
c) the acrylate capped polyurethane in an amount in the range of 0.5 to 4 mass% with respect to the total mass of the composition;
d) veova (vinyl decanoate- vinyl monomer) in an amount in the range of 0.5 to 4 mass% with respect to the total mass of the composition;
e) VTMO (vinyl trimethoxy silane- vinyl monomer) in an amount in the range of 0.1 to 1 mass% with respect to the total mass of the composition;
f) sodium lauryl sulfate (a stabilizer) in an amount in the range of 0.01 to 0.1 mass% with respect to the total mass of the composition;
g) a buffer solution of sodium bicarbonate in an amount in the range of 0.01 to 0.1 mass% with respect to the total mass of the composition;
h) BYK 022 (a defomer) in an amount in the range of 0.1 to 1 mass% with respect to the total mass of the composition; and
i) an initiator in an amount in the range of 0.02 to 1 mass% with respect to the total mass of the composition;
wherein the capped polyurethane is in-situ grafted with vinyl polymer.
In an exemplary embodiment of the present disclosure, the copolymer composition comprises:
a) vinyl acetate (vinyl monomer) in an amount of 42 mass% with respect to the total mass of the composition;
b) polyvinyl alcohol in an amount of 5 mass% with respect to the total mass of the composition;
c) the acrylate capped polyurethane in an amount of 0.5 mass% with respect to the total mass of the composition;
d) sodium lauryl sulfate (a stabilizer) in an amount of 0.1 mass% with respect to the total mass of the composition;
e) a buffer solution of sodium bicarbonate in an amount of 0.05 mass% with respect to the total mass of the composition;
f) BYK 022 (a defomer) in an amount of 0.3 mass% with respect to the total mass of the composition;
g) ammonium persulphate (an initiator) in an amount of 0.05 mass% with respect to the total mass of the composition; and
h) sodium metabisulphite (an initiator) in an amount of 0.05 mass% with respect to the total mass of the composition;
wherein the capped polyurethane is in-situ grafted with vinyl polymer.
In another exemplary embodiment of the present disclosure, the copolymer composition comprises:
a) vinyl acetate (vinyl monomer) in an amount of 42 mass% with respect to the total mass of the composition;
b) polyvinyl alcohol in an amount of 5 mass% with respect to the total mass of the composition;
c) the acrylate capped polyurethane in an amount of 2 mass% with respect to the total mass of the composition;
d) butyl acrylate (acrylic monomer) in an amount of 0.2 mass% with respect to the total mass of the composition;
e) sodium lauryl sulfate (a stabilizer) in an amount of 0.1 mass% with respect to the total mass of the composition;
f) a buffer solution of sodium bicarbonate in an amount of 0.05 mass% with respect to the total mass of the composition;
g) BYK 022 (a defomer) in an amount of 0.3 mass% with respect to the total mass of the composition;
h) ammonium persulphate (an initiator) in an amount of 0.05 mass% with respect to the total mass of the composition; and
i) sodium metabisulphite (an initiator) in an amount of 0.05 mass% with respect to the total mass of the composition;
wherein the capped polyurethane is in-situ grafted with vinyl-acrylic polymer.
The copolymer composition of the present application can be used in coating, adhesive and sealant application.
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 illustrated herein below with the help of the following experiments. The experiments used herein are intended merely to facilitate an understanding of the 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 experiments should not be construed as limiting the scope of embodiments herein. These laboratory scale experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial/commercial scale.
EXPERIMENTAL DETAILS
Experiment-1: Synthesis of the capped polyurethane (CPU) in accordance with the present disclosure
General procedure: A predetermined amount of polyol was charged in a reactor fitted with stirrer, reflux condenser, nitrogen inlet and a thermocouple. Nitrogen gas was charged in the reactor with a constant flow followed by dropwise addition of a predetermined amount of mono or polymeric isocyanate under stirring for 40 minutes to obtain a mixture. After completion of isocyanate addition, di(n-butyl) tin dilaurate catalyst was added to the mixture and the temperature was raised slowly up to 100 °C and the same temperature was maintained till theoretical % NCO was obtained. After desired % NCO was obtained, the reaction temperature was reduced to 50 °C. Hydroxyl acrylate/methacrylate was added slowly to the mixture over a time period of 40 minutes to obtain a first mass. After complete addition of hydroxyl acrylate, the temperature was maintained at 50 °C for 2 hours to obtain a second mass. Isopropyl alcohol (IPA) was added slowly to the second mass over a time period of 40 minutes optionally, followed by adding a modifier and the temperature was maintained at 50 °C for 2 hours followed by cooling down to 40 °C to obtain the capped polyurethane (CPU).
The specific amount (mass%) of the specific components of CPU formulation are presented in Table-1.
Table-1: Formulations of capped polyurethane (CPU) of different backbones
Ingredients Mass (%)
CPU-1 CPU-2 CPU-3 CPU-4 CPU-5 CPU-6 CPU-7 CPU-8 CPU-9 CPU-10 CPU-11 CPU-12 CPU-13 CPU-14 CPU-15 CPU-16 CPU-17
Polyol-1000 (Polypropylene glycol) -- 25.00 26.00 19.00 15.00 18.00 23.00 18.00
Polyol-2000(Polypropylene glycol) 72.00 40.97 75.08 52.12 50.67 72.00 42.52 67.46 73.59 74.23 75.23 71 71 71
Polyol-2000 (Polyester Polyol) -- -- 45.18 -- -- -- 54.05 -- -- 53.70 -- --
Isophorone diisocyanate 16.10 20.22 16.58 -- -- -- -- 16.01 19.68 -- -- -- -- 16.12 16.16 16.10
Hexamethylene diisocyanate -- -- -- 12.63 15.16 -- -- -- -- 11.35 12.38 12.48 12.65
Desmodur 44V 20L (diphenylmethane diisocyanate) -- -- -- -- 21.51 16.81 -- -- -- -- 16.76 -- --
Di(n-butyl)tin dilaurate 0.03 0.03 0.03 -- -- -- -- 0.03 0.03 -- -- -- -- -- 0.03 0.03 0.03
Hydroxypropyl acrylate -- -- -- -- -- -- -- 4.69 -- -- -- -- --
Hydroxyethyl methacrylate 4.69 5.92 4.85 4.89 5.86 5.25 4.10 7.00 -- -- -- -- -- 4.68 4.66 4.69
Polyethylene
glycol Monomethacrylate -- -- -- -- -- -- -- -- -- 11.80 -- -- -- --
N-
Hydroxyethyl acrylamide -- -- -- -- -- -- -- -- -- -- 4.24 -- 4.27 4.33
N-(2-Hydroxypropyl) methacrylamide -- -- -- -- -- -- -- -- -- -- 4.50 -- --
Isopropyl alcohol 7.18 7.86 7.36 7.40 7.86 7.57 7.04 7.27 7.77 -- -- -- -- -- 7.08 7.71
Isobutyl alcohol -- -- -- -- -- -- -- -- -- 7.79
Isooctyl alcohol -- -- -- -- -- -- -- -- -- 9.39 9.79 7.04
Benzyl alcohol -- -- -- -- -- -- -- -- -- -- -- -- 9.02
Bisphenol A epoxy (modifier) 1.1
Silres SY 300
(silanol functional phenyl-propyl polysiloxane)- (modifier) 1.0
Aminosilane (modifier) 8.18
Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00
Experiment-2: Synthesis of CPU grafted polyvinyl acetate polymer (the copolymer composition) in accordance with the present disclosure
Example-1
4 parts of polyvinyl alcohol and 38 parts of demineralized water were charged into a reactor fitted with stirrer, thermocouple and reflux condenser and was stirred at 90 °C for 5 hours followed by cooling to 60 °C to obtain a first mixture. Separately, 0.5 parts CPU-1, 46 parts vinyl acetate, 4 parts vinyl decanoate, 0.2 part vinyl trimethoxy silane were mixed to obtain a second mixture. 0.05 parts of a sodium bicarbonate buffer solution and 5 % of the second mixture were added to the first mixture in the reactor as a seed along with simultaneous addition of 1.1 parts each of 4.5 % solution of ammonium persulfate and sodium metabisulfite at 60 °C for 15 minutes to obtain a third mixture. Remaining 95 % of the second mixture was added dropwise for 6 hours to the third mixture along with simultaneous addition of 2.6 parts of 2 % solution of ammonium persulfate and sodium metabisulfite followed by digesting the contents in the reactor for 1 hour at 60 °C to obtain a fourth mixture. 0.05 parts each of a solution of sodium formaldehyde sulfoxylate and tert-butyl hydro peroxide (chaser catalysts) were added to the fourth mixture at 60 °C under stirring for 30 minutes to obtain a slurry. Then the contents in reactor were cooled to 40 °C. 0.04 part of remaining additives (In can stabilizer : a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150) and BYK 022 (Defoamer)) and 0.02 part ammonia buffer solution were added and stirred for another 15 minutes to obtain a product mixture. The product mixture was filtered to obtain the copolymer composition (CPU grafted vinyl copolymer).
(*1 part=1 mass%)
Example-2
5 parts of polyvinyl alcohol and 38 parts of demineralized water were charged into a reactor fitted with stirrer, thermocouple and reflux condenser and was stirred at 90 °C for 5 hours followed by cooling to 60 °C to obtain a first mixture. Separately, 2 parts CPU-1, 44 parts vinyl acetate, 4 parts vinyl decanoate, 0.2 part vinyl trimethoxy silane were mixed to obtain a second mixture. 0.05 parts of a sodium bicarbonate buffer solution and 5 % of the second mixture were added to the first mixture in the reactor as a seed along with 1.1 each parts of 4.5 % solution of ammonium persulfate and sodium metabisulfite at 60 °C for 15 minutes to obtain a third mixture. Remaining 95 % of the second mixture was added dropwise for 6 hours to the third mixture along with simultaneous addition of 2.6 parts of 2 % solution of ammonium persulfate and sodium metabisulfite followed by digesting the contents in the reactor for 1 hour at 60 °C to obtain a fourth mixture. 0.05 parts each of a solution of sodium formaldehyde sulfoxylate and tert-butyl hydro peroxide (chaser catalysts) were added to the fourth mixture at 60 °C under stirring for 30 minutes to obtain a slurry. Then the contents in reactor were cooled to 40 °C. 0.04 part of remaining additives (In can stabilizer : a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150) and BYK 022 (Defoamer)) and 0.02 part ammonia buffer solution) were added and stirred for another 15 minutes to obtain a product mixture. The product mixture was filtered to obtain the copolymer composition (CPU grafted vinyl copolymer).
(*1 part=1 mass%)
Example-3
5 parts of polyvinyl alcohol and 38 parts of demineralized water were charged into a reactor fitted with stirrer, thermocouple and reflux condenser and was stirred at 90 °C for 5 hours followed by cooling to 60 °C to obtain a first mixture. Separately, 5 parts CPU-1, 44.5 parts vinyl acetate, 4 parts vinyl decanoate, 0.2 part vinyl trimethoxy silane were mixed to obtain a second mixture. 0.05 parts of a sodium bicarbonate buffer solution and 5 % of the second mixture were added to the first mixture in the reactor as a seed along with 1.1 parts each of 4.5 % solution of ammonium persulfate and sodium metabisulfite at 60 °C for 15 minutes to obtain a third mixture. Remaining 95 % the second mixture was added dropwise for 6 hours to the third mixture along with simultaneous addition of 2.6 parts of 2 % solution of ammonium persulfate and sodium metabisulfite followed by digesting the contents in the reactor for 1 hour at 60 °C to obtain a fourth mixture. 0.05 parts each of a solution of sodium formaldehyde sulfoxylate and tert-butyl hydro peroxide (chaser catalysts) were added to the fourth mixture at 60 °C under stirring for 30 minutes to obtain a slurry. Then the contents in reactor were cooled to 40 °C. 0.04 part of remaining additives (In can stabilizer: a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150) and BYK 022 (Defoamer)) and 0.02 part ammonia buffer solution were added and stirred for another 15 minutes to obtain a product mixture. The product mixture was filtered to obtain the copolymer composition (CPU grafted vinyl copolymer).
(*1 part=1 mass%)
Example-4
5 parts of polyvinyl alcohol and 38 parts of demineralized water were charged into a reactor fitted with stirrer, thermocouple and reflux condenser and was stirred at 90 °C for 5 hours followed by cooling to 60 °C to obtain a first mixture. Separately, 2 parts CPU-1, 44.5 parts vinyl acetate, 0.2 part butyl acrylate, 4 parts vinyl decanoate, 0.2 part vinyl trimethoxy silane were mixed to obtain a second mixture. 0.05 parts of a sodium bicarbonate buffer solution and 5 % of the second mixture were added to the first mixture in the reactor as a seed along with 1.1 parts each of 4.5 % solution of ammonium persulfate and sodium metabisulfite at 60 °C for 15 minutes to obtain a third mixture. Remaining 95 % the second mixture was added dropwise for 6 hours to the third mixture along with simultaneous addition of 2.6 parts of 2 % solution of ammonium persulfate and sodium metabisulfite followed by digesting the contents in the reactor for 1 hour at 60 °C to obtain a fourth mixture. 0.05 parts each of a solution of sodium formaldehyde sulfoxylate and tert-butyl hydro peroxide (chaser catalysts) were added to the fourth mixture at 60 °C under stirring for 30 minutes to obtain a slurry. Then the contents in reactor were cooled to 40 °C. 0.04 part of remaining additives (In can stabilizer: a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150) and BYK 022 (Defoamer)) and 0.02 part ammonia buffer solution were added and stirred for another 15 minutes to obtain a product mixture. The product mixture was filtered to obtain the copolymer composition (CPU grafted vinyl-acrylic copolymer).
(*1 part=1 mass%)
Example: 5-19
5 parts of polyvinyl alcohol and 38 parts of demineralized water were charged into a reactor fitted with stirrer, thermocouple and reflux condenser and was stirred at 90 °C for 5 hours followed by cooling to 60 °C to obtain a first mixture. Separately, 2 parts CPU (CPU-2 to CPU-17), 44 parts vinyl acetate, 4 parts vinyl decanoate, 0.2 part vinyl trimethoxy silane were mixed to obtain a second mixture. 0.05 parts of a sodium bicarbonate buffer solution and 5 % of the second mixture were added to the first mixture in the reactor as a seed along with 1.1 parts each of 4.5 % solution of ammonium persulfate and sodium metabisulfite at 60 °C for 15 minutes to obtain a third mixture. Remaining 95 % of the second mixture was added dropwise for 6 hours to the third mixture along with simultaneous addition of 2.6 parts of 2 % solution of ammonium persulfate and sodium metabisulfite followed by digesting the contents in the reactor for 1 hour at 60 °C to obtain a fourth mixture. 0.05 parts each of a solution of sodium formaldehyde sulfoxylate and tert-butyl hydro peroxide (chaser catalysts) were added to the fourth mixture at 60 °C under stirring for 30 minutes to obtain a slurry. Then the contents in reactor were cooled to 40 °C. 0.04 part of remaining additives (In can stabilizer: a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150) and BYK 022 (Defoamer)) and 0.02 part ammonia buffer solution were added and stirred for another 15 minutes to obtain a product mixture. The product mixture was filtered to obtain the copolymer composition (CPU grafted vinyl copolymer).
(*1 part=1 mass%)
Comparative example (without use of CPU)
5 parts of polyvinyl alcohol and 38 parts of demineralized water were charged into a reactor fitted with stirrer, thermocouple and reflux condenser and was stirred at 90 °C for 5 hours followed by cooling to 60 °C to obtain a first mixture. Separately, 47 parts vinyl acetate, 4 parts vinyl decanoate, 0.2 part vinyl trimethoxy silane were mixed to obtain a second mixture. 0.05 parts of a sodium bicarbonate buffer solution and 5 % of the second mixture were added to the first mixture in the reactor as a seed along with 1.1 parts each of 4.5 % solution of ammonium persulfate and sodium metabisulfite at 60 °C for 15 minutes to obtain a third mixture. Remaining 95 % of the second mixture was added dropwise for 6 hours to the third mixture along with simultaneous addition of 2.6 parts of 2 % solution of ammonium persulfate and sodium metabisulfite followed by digesting the contents in the reactor for 1 hour at 60 °C to obtain a fourth mixture. 0.05 parts each of a solution of sodium formaldehyde sulfoxylate and tert-butyl hydro peroxide (chaser catalysts) were added to the fourth mixture at 60 °C under stirring for 30 minutes to obtain a slurry. Then the contents in reactor were cooled to 40 °C. 0.04 part of remaining additives (In can stabilizer : a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150) and BYK 022 (Defoamer)) and 0.02 part ammonia buffer solution were added and stirred for another 15 minutes to obtain a product mixture. The product mixture was filtered to obtain the copolymer composition (CPU grafted vinyl copolymer).
(*1 part=1 mass%)
Experiment-3: Physical and performance evaluation data of CPU grafted polyvinyl acetate polymer
Physical properties such as viscosity, accelerated stability and mechanical/performance properties such as lap-shear strength and water immersion resistance were tested for the CPU grafted vinyl polymers and CPU grafted vinyl-acrylic polymers of the present disclosure. As per European standards BS EN-204, the prepared copolymer composition was tested for their D3 performance in adhesive formulation. The formulated adhesives were applied on the wood specimens and dried for 7 days at standard ambient conditions. After 7 days, specimens were immersed in cold water for 4 days and tested the lap shear strength.
The results are presented in Table-2.
Table-2: Physical and mechanical properties based on different CPU designs in terms of accelerated stability, water resistance, lap shear strength and Lab shear strength after D3 testing.
Example CPU Design details (Parts used) Viscosity at 30° C (Poise) Stability at 55° C
for 3 months Lap shear strength (MPa) Water immersion resistance
for one month D3 durability
= 2MPa lap shear strength Boiling water resistance( 6 h dip @ 95 °C
Example-1 CPU-1 (0.5 Parts) 70 Stable 10.60 No blisters 2.5 No detachment
Example-2 CPU-1 (2 Parts) 67.5 Stable 12.60 No blisters 2.5 No detachment
Example-3 CPU-1 (5Parts) 75 Stable 13.70 No blisters 2.6 No detachment
Example-4 CPU-2 (2 Parts) 90 Stable 12.75 No blisters 2.5 No detachment
Example-5 CPU-3 (2 Parts) 70 Stable 12.00 No blisters 3.33 No detachment
Example-6 CPU-4 (2 Parts) 80 Stable 11.37 No blisters 2.7 No detachment
Example-7 CPU-5 (2 Parts) 72.5 Stable 8.90 No blisters 2,0 No detachment
Example-8 CPU-6 (2 Parts) 65 Stable 9.00 No blisters 2 No detachment
Example-9 CPU-7 (2 Parts) 80 Stable 10.00 No blisters 2 No detachment
Example-10 CPU-8 (2 Parts) 71.5 Stable 9.50 No blisters 1.5 Detachment after 4 hours
Example-11 CPU-9 (2 Parts) 80 Stable 12.60 No blisters 2.5 No detachment
Example-12 CPU-10 (2 Parts) 75 Stable 10.00 No blisters 2.1 No detachment
Example-13 CPU-11 (2 Parts) 75 Stable 8.78 No blisters 1.9 No detachment
Example-14 CPU-12(2 Parts) 70 Stable 8.83 No blisters 2.1 No detachment
Example-15 CPU-13 (2 Parts) 80 Stable 11.84 No blisters 2.9 No detachment
Example-16 CPU-14 (2 Parts) 80 Stable 11.84 No blisters 2.9 No detachment
Example-17 CPU-15 (2 Parts) 90 Stable 10.96 No blisters 2.1 No detachment
Example-18 CPU-16 (2 Parts) 100 Stable 11.08 No blisters 2.4 No detachment
Example-19 CPU-17 (2 Parts) 95 Stable 10.78 No blisters 2.2 No detachment
Comparative Example Without CPU 120 Viscosity pick two times 9.1 Blisters 0.2 Detachment within one hour
From Table 2, it is observed that the adhesive formulation comprising CPU grafted vinyl/ vinyl-acrylic copolymer composition of the present disclosure is stable at 55° C for 3 months which indicate that the copolymer composition of the present disclosure has a minimum twelve-month of shelf life. Further, the copolymer composition of the present disclosure is found to have excellent cold water (passes D3 durability test) and boiling water resistance and increased mechanical properties (lap shear strength in the range of 8.78 MPa to 12.75 MPa). Overall, the copolymer composition of the present disclosure is found to have a balance in properties such as elongation and tensile strength with excellent water resistance without using any additional cross-linkers.
Furthermore, from Table 2, it can be inferred that the copolymer composition of the present disclosure has faster handling strength as it passes D3 durability test which indicates that the copolymer composition when coated on a substrate, the coating dries within 30-45 minutes and the substrate is ready to handle in 30-45 minutes for further purpose.
TECHNICAL ADVANCEMENTS
The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a copolymer composition that has:
• stable viscosity with a minimum twelve-month of shelf life;
• excellent cold water and boiling water resistance;
• increased mechanical properties such as lap shear strength;
• balance in properties of lap shear strength with excellent water resistance; and
• circumvents the use of any additional cross-linkers.
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.
,CLAIMS:WE CLAIM:
1) A copolymer composition comprising;
a. a capped polyurethane;
b. one of a polymer selected from vinyl polymer and a combination of vinyl and acrylic polymer;
c. a polyvinyl alcohol polymer;
d. a defoamer;
e. a buffer;
f. a stabilizer;
g. an initiator; and
h. a fluid medium;
wherein said capped polyurethane is in-situ grafted with said polymer.
2) The composition as claimed in claim 1, wherein at least one end of said capped polyurethane is capped with a capping agent; wherein said capping agent has at least one functionality selected from hydroxyl-acrylate, epoxy, silane and alcohol.
3) The composition as claimed in claim 2, wherein said capping agent having hydroxyl-acrylate functionality is selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, N-hydroxyethyl acrylamide, N-(2-hydroxypropyl)methacrylamide, 3-phenoxy-2-hydroxypropyl methacrylate, glycerol methacrylate and polyethyleneglycol monomethacrylate.
4) The composition as claimed in claim 2, wherein said capping agent having epoxy functionality is selected from diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E and diglycidyl ether of bisphenol-S.
5) The composition as claimed in claim 2, wherein said capping agent having silane functionality is selected from amino silanes; wherein said amino silanes are selected from 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-methyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-triethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride.
6) The composition as claimed in claim 2, wherein said capping agent having alcohol functionality is selected from isopropyl alcohol, isobutyl alcohol, iso-octyl alcohol and benzyl alcohol.
7) The composition as claimed in claim 1, wherein said capped polyurethane has a molecular weight in the range of 1000 to 5000 g/mol.
8) The composition as claimed in claim 1, wherein a backbone of said capped polyurethane is modified by a modifier selected from epoxy functionality component, siloxane functionality component and a combination thereof.
9) The composition as claimed in claim 8, wherein said epoxy functionality component is selected from diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E and diglycidyl ether of bisphenol-S.
10) The composition as claimed in claim 8, wherein said silicone functionality component is selected from silanol functional phenyl-propyl polysiloxane, silanol functional phenyl polysiloxane, silanol functional methyl polysiloxane, dihydroxypolydimethylsiloxane, dihydroxypolydiethylsiloxane and amino silane compounds.
11) The composition as claimed in claim 1, wherein said acrylic polymer is prepared from at least one acrylic monomer selected from methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, 2-ethyl hexyl acrylate and a combination thereof.
12) The composition as claimed in claim 1, wherein said vinyl polymer is prepared from at least one vinyl monomer selected from vinyl acetate, vinyl decanoate, vinyl trimethoxy silane and a combination thereof.
13) The composition as claimed in claims 1, wherein a molecular weight of said polymer is between 1,00,000 g/mol to 300000 g/mol.
14) The composition as claimed in claim 1, wherein a mass ratio of said capped polyurethane to said polymer is in the range of 1:49 to 5:45.
15) The composition as claimed in claim 1, wherein said defoamer is selected from polysiloxne containing polyglycol, polyether siloxane copolymer and organo-silicon polymers and said initiator is selected from ammonium persulfate, potassium persulfate, sodium persulfate and sodium metabisulfite.
16) The composition as claimed in claim 1, wherein said buffer is selected from ammonia buffer, sodium bicarbonate buffer and sodium acetate buffer.
17) The composition as claimed in claim 1, wherein said stabilizer is selected from sodium, potassium, or ammonium salts of fatty acids; C12 - C16 alkyl sulfates selected from sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS); nonionic surfactants selected from poly(ethylene oxide) cellulose and hydroxyethyl cellulose, polyvinyl alcohol and a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one.
18) The composition as claimed in claim 1, wherein said fluid medium is selected from an organic solvent, water and a combination thereof; wherein said organic solvent is selected from 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-octanol and benzyl alcohol.
19) The composition as claimed in claim 1, wherein said polyurethane grafted vinyl copolymer composition and said polyurethane grafted vinyl-acrylic copolymer composition has a viscosity lower than non-grafted vinyl copolymer or vinyl-acrylic copolymer, by 30 to 40 poise.
20) A process for the preparation of a copolymer composition, said process comprising the following steps:
i. obtaining a capped polyurethane;
ii. separately, dissolving polyvinyl alcohol in a fluid medium in a reactor at a first predetermined temperature under stirring for a first predetermined time period to obtain a first mixture;
iii. separately, mixing a predetermined amount of at least one monomer with a predetermined amount of said capped polyurethane to obtain a second mixture;
iv. adding a first buffer solution and a first predetermined amount of said second mixture to said first mixture, followed by adding a first predetermined amount of at least one initiator at a second predetermined temperature and stirring for a second predetermined time period to obtain a third mixture;
v. gradually adding a second predetermined amount of said second mixture and a second predetermined amount of said at least one initiator to said third mixture over a third predetermined time period and reacting in the presence of a chaser catalyst at a third predetermined temperature to obtain a slurry; and
vi. adding predetermined amounts of a stabilizer, a defomer and a second buffer solution to said slurry at a fourth predetermined temperature under stirring for a fourth predetermined time period to obtain said copolymer composition.
21) The process as claimed in claim 20, wherein said capped polyurethane is obtained by mixing and reacting a predetermined amount of a polyol with a predetermined amount of a diisocyanate monomer in a predetermined ratio, in the presence of a predetermined amount of a water compatible hydroxyl terminated solvent, a predetermined amount of a capping agent, optionally, a predetermined amount of a modifier and optionally, a predetermined amount of a catalyst, at a temperature in a range of 50 °C to 100 °C to obtain said capped polyurethane.
22) The process as claimed in claim 21, wherein said polyol is selected from polyether polyol, polycarbonate polyol, polyester polyol, poly(tetramethylene ether) glycol and a combination thereof and wherein said predetermined amount of said polyol is in the range of 50 mass% to 70 mass% with respect to the total mass of the capped polyurethane; said diisocyanate monomer is selected from an isophorone diisocyanate, hexamethylene diisocyanate, hydrogenated toluene diisocyanate, toluene diisocyanate, hydrogenated diphenylmethane diisocyanate and diphenylmethane diisocyanate and said predetermined amount of said diisocyanate monomer is in the range of 15 mass% to 25 mass% with respect to the total mass of the capped polyurethane and wherein said predetermined ratio of said polyol to said diisocyanate is in the range of 1:1.2 to 1: 2.2.
23) The process as claimed in claim 21, wherein said capping agent is selected from diisocyanatehydroxyethyl acrylate, hydroxylpropyl acrylate, hydroxylbutyl acrylate, hydroxylethyl methacrylate, hydroxylpropyl methacrylate, hydroxylbutyl methacrylate, N-hydroxyethyl acrylamide, N-(2-Hydroxypropyl)methacrylamide, 3-phenoxy-2-hydroxypropyl methacrylate, glycerol methacrylate, polyethyleneglycol monomethacrylate, diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E, diglycidyl ether of bisphenol-S, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-methyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyl-triethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, isopropyl alcohol, isobutyl alcohol, iso-octyl alcohol and benzyl alcohol and wherein said predetermined amount of said capping agent is in the range of 2 mass% to 7 mass% with respect to the mass of the capped polyurethane.
24) The process as claimed in claim 21, wherein said modifier is selected from diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol-AP, diglycidyl ether of bisphenol-C, diglycidyl ether of bisphenol-E, diglycidyl ether of bisphenol-S, silanol functional phenyl-propyl polysiloxane (Silres SY 300), silanol functional phenyl polysiloxane, silanol functional methyl polysiloxane, dihydroxypolydimethylsiloxane, dihydroxypolydiethylsiloxane and amino silane compounds.
25) The process as claimed in claim 21, wherein said water compatible hydroxyl terminated solvent is alcohol and said predetermined amount of said water compatible hydroxyl terminated solvent is in the range of 3 mass% to 8 mass% with respect to the total mass of the capped polyurethane.
26) The process as claimed in claim 21, wherein said catalyst is selected from dibutyl tin dilaurate, dibutyltin diacetate, dimethyltin dioleate, dibutyltin dimaleate and dioctyltin dilaurate and said predetermined amount of said catalyst is in the range of 0.01 mass% to 0.1 mass% with respect to the total mass of the capped polyurethane.
27) The process as claimed in claim 20, wherein said fluid medium is selected from an organic solvent, water and a combination thereof; wherein said organic solvent is selected from 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-octanol and benzyl alcohol and wherein said predetermined amount of said fluid medium is in the range of 1 mass% to 6 mass%.
28) The process as claimed in claim 20, wherein said stabilizer is selected from sodium, potassium, and ammonium salt of fatty acids, C12 - C16 alkyl sulfates selected from sodium dodecyl sulfate (SDS), sodium lauryl sulfate (SLS), nonionic surfactants selected from poly(ethylene oxide) and hydroxyethyl cellulose, polyvinyl alcohol and a mixture of 5-chloro-2-methyl-4- isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (Kathon LX 150); and wherein said predetermined amount of said stabilizer is in the range of 0.1 mass% to 1 mass%.
29) The process as claimed in claim 20, wherein said defoamer is selected from polysiloxne containing polyglycol, polyether siloxane copolymer and organo-silicon polymers; and said predetermined amount of said defoamer is in the range of 0.1 mass% to 0.4 mass%.
30) The process as claimed in claim 20, wherein said first predetermined temperature is in the range of 70 °C to 100 °C and said first predetermined time period is in the range of 4 hours to 7 hours; said second predetermined temperature is in the range of 50 °C to 70 °C; said second predetermined time period is in the range of 10 minutes to 30 minutes; said third predetermined temperature is in the range of 50 °C to 70 °C; said third predetermined time period is in the range of 4 hours to 8 hours; said fourth predetermined temperature is in the range of 25 °C to 45 °C; and said fourth predetermined time period is in the range of 10 minutes to 30 minutes.
31) The process as claimed in claim 20, wherein said monomer is selected from vinyl monomers and acrylic monomers; and wherein said predetermined amount of said monomer is in the range of 40 mass% to 47 mass%.
32) The process as claimed in claim 30, wherein said vinyl monomer is selected from vinyl acetate, vinyl decanoate, vinyl trimethoxy silane and a combination thereof.
33) The process as claimed in claim 30, wherein said acrylic monomer is selected from methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, 2-ethyl hexyl acrylate and a combination thereof.
34) The process as claimed in claim 20, wherein said initiator is selected from ammonium persulfate, potassium persulfate, sodium persulfate and sodium metabisulfite; wherein said predetermined amount of said initiator is in the range of 0.05 mass% to 0.3 mass% and said chaser catalyst is selected from ammonium persulfate, potassium persulfate, sodium persulfate and hydrogen peroxide, tert-Butyl hydroperoxide; wherein said predetermined amount of said chaser catalyst is in the range of 0.025 mass% to 0.05 mass%.
35) The process as claimed in claim 20, wherein said first buffer is selected from sodium bicarbonate buffer and sodium acetate buffer and said second buffer is selected from ammonia buffer, sodium bicarbonate buffer and sodium acetate buffer.

Dated this 2nd day of December, 2021

_______________________________
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