Description:FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
[See section 10, Rule 13]

A POLYMER COMPOSITION COMPRISING A MODIFIED ACRYLIC POLYOL AND A METHOD OF PREPARATION THEREOF

PPG ASIAN PAINTS PRIVATE LIMITED WHOSE ADDRESS IS 6A, SHANTINAGAR, SANTACRUZ EAST, MUMBAI 400055, MUMBAI, MAHARASHTRA, INDIA.

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

FIELD OF INVENTION
The invention relates to a polymer composition comprising a modified acrylic polyol resin and cellulose acetate butyrate, its method of preparation and a polyurethane composition kit comprising the polymer composition.

BACKGROUND OF THE INVENTION
Conventionally, a primer is required to be applied to the substrate during painting or coating before the application of a finish coat for providing better adhesion of the finish coat on the substrate.

Primer lays the foundation of a paint job and can be used on different substrates such as glass, sheet metal, floor/tiles, fiber-reinforced polymer (FRP), wood, drywall and concrete. Primer is a synthetic polymer (resin) and different substrates require primers having different chemistry.

A paint or coating composition is also a polymer composition. Specifically, polyurethane coating compositions are acrylic polymer compositions. A polyurethane coating is formed by mixing the acrylic polymer composition with a hardener and then applying the mixture on the substrate.

The chemical nature of primer is different from the polymer composition for coating and therefore, a careful selection of primer and polymer composition is required for adhesion on different substrates. A combination of a primer and a polymer composition suitable for one type of substrate may not provide desirable adhesion of the coating on other type of substrates.

WO2009/015281 relates to a coating composition for metal substrate comprising: a polymer having dual functional groups such as an epoxy, a hydroxyl, a carboxylic acid or a surfactant moiety; and a crosslinking agent selected from the group consisting of epoxy, isocyanate, amino, amine and anhydride functional resins.

WO2018/114991 relates to a polyurethane composition comprising a polyol component containing at least one polyol and a hardener component comprising at least one polyisocyanate. The composition is casted in a mold and the cured to obtain a pre-manufactured article having a pattern imitating word or concrete. The pre-manufactured article is then applied on a substrate.

US 2021/371693 relates to a two component clearcoat composition comprising a first component containing a hydroxyl functional resin and a second component comprising a cross linking agent being a first isocyanate resin which is not blocked, and a blocked isocyanate resin that is a reacted form of a second isocyanate resin and a blocking agent. This composition changes the visual appearance of the objected coated with a basecoat.

WO2020/129024 relates to a multilayer polyurethane surfacing film. The film comprises a first clear coat comprising a crosslinked polyurethane; a second clear coat layer comprising a crosslinked polymer that is essentially free of hydroxy functional silicone poly (meth) acrylate; a bulk layer comprising a thermoplastic polyurethane; and an adhesive layer. The films can be applied to a substrate and is useful in paint protection and paint replacement applications.

US 2021/0189050 relates to a non-aqueous cross linkable two component polyurethane composition comprising a binder module comprising the polyol and a cross linker module comprising a cross linking agent. The document describes that when the composition is used as a clear coat it is preferably applied over a colour and/or effect - imparting base coat.

US 2021/0155733 relates to a composition for forming polyurethane film having self-healing recovery by comprising an OH group containing polymer, an amphoteric ion-based polymer and a isocyanate-based compound as a curing agent.

The above documents describe that a primer or basecoat is required for better adhesion of the polyurethane coating on the substrate. To make the painting process user and environmentally friendly, there is a need to reduce the use of volatile solvents. Also, there is a need to simplify the painting process by reducing the steps involved. A solution for the same is to eliminate the primer coating step, this will not only reduce the use of volatile solvent but also hasten the painting process. However, as the primer provides better adhesion of the paint to the substrate, there is a need for a polymer composition that provides acceptable adhesion on any substrate in absence of a primer.

SUMMARY OF THE INVENTION
The present invention relates to a polymer composition comprising a modified acrylic polyol resin, a hydroxy functional acrylic resin and cellulose acetate butyrate.

In an aspect, the present invention relates to a polymer composition comprising 10%-40% by weight of the modified acrylic polyol resin, 20%-50% by weight of a hydroxy functional acrylic resin and 0.2%-2% by weight of cellulose acetate butyrate.

In another aspect, the present invention relates to a process for preparation of a polymer composition. The process comprises blending a modified acrylic polyol resin and a hydroxyl functional acrylic resin to form a mix. Then, adding cellulose acetate butyrate to form the polymer composition.

In another aspect, the present invention relates to a two component (2K) polyurethane composition kit comprising the polymer composition and an isocyanate hardener.

In a further aspect, the present invention relates to a process for preparation of the modified acrylic polyol resin. The process comprises:
- providing a reactor containing a hydrocarbon solvent;
- preparing a monomer mix by mixing an acrylic acid based monomer, a reactive diluent, 2-hydroxyethyl methacrylate phosphate, a salt of acrylic acid and an unsaturated carboxylic acid;
- adding an initiator to the monomer mix;
- adding the monomer mix containing the initiator to the reactor;
- adding a chaser to the reactor; and
- heating the reactor at a temperature in a range of 132°C-135°C to form the modified acrylic resin.

DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a polymer composition comprising a modified acrylic polyol resin, a hydroxy functional acrylic resin and cellulose acetate butyrate.

The polymer composition comprises 10%-40% by weight of the modified acrylic polyol resin, 20%-50% by weight of the hydroxyl functional acrylic resin, and 0.2%-2% by weight of cellulose acetate butyrate.

The hydroxy functional acrylic resin is represented by the formula R-CH2-OH, where R is selected by altering the monomers to achieve the desired hardness and flexibility. In an embodiment, the hydroxy functional acrylic resin is a compound having R as -CH2-CO-COOCH3-CH2-COOCH3-CH2- based on methyl methacrylate (MMA) and 2-Hydroxyethyl methacrylate (HEMA) monomers.

Cellulose acetate butyrate present in the polymer composition has a low molecular weight. The number average molecular weight (Mn) of cellulose acetate butyrate is in a range of 20,000 to 50,000, preferably the number average molecular weight is 30,000. Cellulose acetate butyrate is present in the polymer composition in the form of a solution. The polymer composition comprises 1%-10% by weight of cellulose acetate butyrate solution.

The polymer composition includes additional components selected from a UV light absorber, a stabilizer, a catalyst, a levelling additive, a surfactant, a coupling agent, an adhesion promoter, a corrosion inhibitor, an epoxy resin, a hydrocarbon solvent or a combination thereof. The sum of the percentages of all the components present in the polymer composition is 100% by weight.

The polymer composition comprises 1%-5% by weight of a UV light absorber, 1%-5% by weight of a stabilizer, 0.1%-1% by weight of a catalyst, 0.1%-1% by weight of a levelling additive, 0.1%-0.5% by weight of a surfactant, 0.3%-1.5% by weight of a coupling agent, 1%-5% by weight of an adhesion promoter, 0.5%-2.5% by weight of a corrosion inhibitor, 0.5%-5% by weight of an epoxy resin, and 10%-40% by weight of a hydrocarbon solvent selected from aromatic hydrocarbon solvent, aliphatic hydrocarbon solvent or a combination thereof. The sum of the percentages of all the components present in the polymer composition is 100% by weight.

In an embodiment, the polymer composition comprises 20%-30% by weight of the modified acrylic polyol resin, 30%-40% by weight of the hydroxyl functional acrylic resin, 3%-9% by weight of a solution of cellulose acetate butyrate, 2%-4% by weight of the UV light absorber, 1%-3% by weight of the stabilizer, 0.3%-0.9% by weight of the catalyst, 0.2%-0.6% by weight of the levelling additive, 0.1%-0.5% by weight of the surfactant, 0.5%-1.0% by weight of the coupling agent, 2%-4% by weight of the adhesion promoter, 1%-2% by weight of the corrosion inhibitor, 1%-3% by weight of the epoxy resin, 10%-15% by weight of the aromatic hydrocarbon solvent and 10%-15% by weight of the aliphatic hydrocarbon solvent. The sum of the percentages of all the components present in the polymer composition is 100% by weight.

The hydroxy functional acrylic resin includes but is not limited to a resin available under the tradename of SYNOCURE 867SD.

The UV light absorber includes but is not limited to hydroxyphenyl benzotriazole available under the tradename of TINUVIN 1130.

The stabilizer includes but is not limited to a light stabilizer that is a mixture of bis (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) sebacate and methyl 1, 2, 2, 6, 6- pentamethyl-4-piperidyl sebacate available under the tradename of TINUVIN 292.

The catalyst includes but is not limited to di-butyl tin laurate (DBDTL).

The levelling agent includes but is not limited to a polyacrylate copolymer available under the tradename BYK358.

The surfactant includes but is not limited to polyether-modified polydimethylsiloxane available under the tradename of BYK306.

The coupling agent includes but is not limited to epoxy functional silane available under the tradename of SILANE A187.

The adhesion promoter includes but is not limited to a salt of a polymer with acidic groups available under the tradename of BYK 4509.

The corrosion inhibitor includes but is not limited to a water free liquid organic-inorganic sol-gel available under the tradename of HALOX 555WF.

The epoxy resin includes but is not limited to type-1 epoxy resin available under the tradename of LAPOX 101.

The aromatic hydrocarbon solvent includes but is not limited to mixed xylene. The aliphatic hydrocarbon solvent includes but is not limited to butyl acetate.

The polymer composition comprising the modified acrylic polyol, hydroxyl functional acrylic resin and cellulose acetate butyrate provides acceptable adhesion of the coating on different substrates such as glass, sheet metal, floor/tiles, wood and FRP composites without the need for a primer. Thereby, the polymer composition acts as a universal coating composition.

The present invention also relates to a process for preparation of the polymer composition. The process comprises blending a modified acrylic polyol resin, and a hydroxyl functional acrylic resin to form a mix. Then, adding cellulose acetate to form a polymer composition.

The process for preparation of a polymer composition comprising additional components as described above comprises mixing a modified acrylic polyol resin, a hydroxyl functional acrylic resin, an epoxy resin and an aromatic solvent to form a solution. Then, adding cellulose acetate butyrate, a UV light absorber, a stabilizer, a catalyst, a levelling additive, a surfactant, a coupling agent, an adhesion promoter, and a corrosion inhibitor to form a clear solution. Then, an aliphatic hydrocarbon solvent is added to the clear solution to adjust the viscosity of the solution.

In an embodiment, 20%-30% by weight of modified acrylic polyol resin, 30%-40% by weight of hydroxy functional acrylic resin, 1%-3% by weight of the epoxy resin (75% solution of type-1 epoxy resin in xylene) and 10%-15% by weight aromatic hydrocarbon solvent preferably mixed xylene are added into a mixer and mixed at 100 rpm for 15-20 minutes.

While continuing stirring, 3%-9% by weight of solution of cellulose acetate butyrate, 2%-4% by weight of hydroxyphenyl benzotriazole, 1%-3% by weight of mixture of bis (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) sebacate and methyl 1, 2, 2, 6, 6- pentamethyl-4-piperidyl sebacate, 0.3%-0.9% by weight of di-butyl tin dilaurate solution, 0.2%-0.6% by weight of solution of polyacrylate copolymer, 0.1%-0.5% by weight of a solution of a polyether-modified polydimethylsiloxane, 0.3%-1% by weight of epoxy functional silane, 2%-4% by weight of salt of a polymer with acidic groups, and 1%-2% by weight of water-free liquid organic-inorganic sol-gel corrosion inhibitor is added to the mixer and mixed at 200-250 rpm for 30 minutes. The solution is checked for clarity and should be clear with no suspension.

The viscosity of the solution is adjusted to 40-60 seconds on Ford viscosity cup B4 with an aliphatic solvent, preferably butyl acetate and stirred for 15 minutes until well-mixed.

The invention also relates to a two component (2K) polyurethane composition kit comprising the polymer composition described above and an isocyanate hardener.

The isocyanate hardener included in the kit is selected from isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI) or a combination thereof.

The invention further relates to a process for coating a substrate by two component (2K) polyurethane composition kit as described above. The process comprises mixing the polymer composition with the isocyanate hardener to form a coating mixture, applying the coating mixture on a substrate and drying to form a polyurethane coating. The coating is air dried or force dried by applying heat.

The polyurethane coating comprises a linkage of Formula I,

-R-COO-NH-COONHR’- (Formula I)
where,
R is -(CH2)6-; and
R’ is -CH2-.

The substrate is selected from glass, wood, sheet metal, fiber-reinforced polymer (FRP) or floor/tiles.

In an embodiment, the isocyanate hardener is HMDI and the process comprises mixing the polymer composition and HMDI in a ratio of 4:1 by volume.

The process by including the polymer composition provides a coating on the substrate by a single coat of the composition. Thereby, the process is simple, convenient and quick as the step of applying a primer is eliminated. This also makes the process economical, environment and operator/user friendly as the process uses less amount of volatile solvent.

Further, the present invention relates to a process for preparation of the modified acrylic polyol resin as described above. The process comprises providing a reactor containing a hydrocarbon solvent. A monomer mix is prepared by mixing an acrylic acid based monomer, a reactive diluent, 2-hydroxyethyl methacrylate phosphate, a monomer, and an unsaturated carboxylic acid. An initiator is added to the monomer mix. Then, the monomer mix containing the initiator is added to the reactor. Followed by addition of a chaser. The rector is heated at a temperature in a range of 132°C-135°C to form the modified acrylic polyol resin.

The hydrocarbon solvent in the reactor is heated to a temperature in a range of 132°C-135°C.

The initiator is added to the monomer mix prior to addition of the monomer mix to the reactor. The monomer mix containing the initiator is added to the reactor over a period of 180 minutes and maintaining the temperature in a range of 132°C-135°C. This is followed by addition of the chaser for a period of 30 mins.

Optionally, if required, mixed xylene is added to the reactor to adjust the percent NVM (non-volatile matter) and viscosity of the modified acrylic polyol resin.

The acrylic acid based monomer includes but is not limited to methyl methacrylate.

The reactive diluent includes but is not limited to styrene.

The monomer includes but is not limited to a salt of acrylic acid such as butyl acrylate available under the tradename of Butyl Acrl-I.

The unsaturated carboxylic acid includes but is not limited to acrylic acid.

The initiator and chaser includes but is not limited to tertiary butyl per benzoate.

The hydrocarbon solvent is an aromatic hydrocarbon solvent as defined above.

In an embodiment the process for preparation of modified acrylic polyol comprises charging the reactor with the hydrocarbon solvent and heating the reactor to a temperature in a range of 132°C-135°C.

Mixing 10%-20% by weight of methyl methacrylate monomer, 15%-25% by weight of styrene monomer, 10%-20% by weight of 2-Hydroxyethyl methacrylate (HEMA) as a phosphate salt i.e., HEMA phosphate, 15%-25% by weight of butyl acrylate and up to 1% (0%-1%) by weight of acrylic acid in a tank to form a monomer mix.

Then, up to 10% (0%-10%) by weight of tertiary butyl per benzoate is added to the monomer mix. After 10-15 minutes of addition of tertiary butyl per benzoate, the monomer mix is added to the reactor at a temperature in range of 132°C-135°C. The addition is carried out uniformly over a period of 180 minutes. Then, an additional amount of tertiary butyl per benzoate is added to the reactor for 30 minutes. After completion of addition of the reactants, the reactor batch is held at a temperature in range of 132°C-135°C till desired viscosity and solid content is achieved. If required, mixed xylene is added to the reactor to adjust the % NVM and viscosity.

The process provides a modified acrylic polyol which is a polymer grafted with acid functional groups. The modified acrylic polyol with the grafted acid functional groups provides better adhesion to the coating on the substrate. A polymer composition comprising the modified acrylic polyol thereby provides a coating having acceptable adhesion on the substrate without requirement of a primer.

EXAMPLES

Example 1: Preparation of modified acrylic polyol of the present invention

A reactor was charged with a hydrocarbon solvent and heated to 135°C.

Preparation of monomer mix
The monomers described in Table 1 below were mixed in a tank to form a monomer mix

Table 1
Monomer Quantity
(% w/w)
MMA monomer (methyl methacrylate) 12-16
Styrene monomer 18-22
2-Hydroxyethyl methacrylate phosphate (HEMA phosphate) 14-16
Butyl acrylate (Butyl Acrl-I) 18-22
Acrylic acid 0-1

0%-10% by weight of tertiary butyl per benzoate as an initiator was added to the monomer mix. After 10-15 minutes of addition of the initiator, the monomer mix was added to the reactor uniformly over a period of 180- minutes while maintaining the temperature of the reactor at 132°C-135°C. After the addition of the monomer mix, tertiary butyl per benzoate as a chaser was added over a period of 30 minutes. The reaction was then carried out at 132°C-135°C till desired viscosity and solids are achieved. The viscosity and percent non-volatile matter (%NVM) of the modified acrylic polyol resin was adjusted if required with mixed xylene.

Example 2: Preparation of a polymer composition of the invention

The components of the polymer composition are described in Table 2, below

Table 2
Raw Material Quantity (% w/w)
Modified acrylic polyol resin prepared in Example 1 25
hydroxy functional acrylic resin (SYNOCURE 867SD) 35
75% solution of solid epoxy resin (type-1) (LAPOX P-101) 1
Mixed xylene 10.9
CAB 551-2 (20% S OL) 6
TINUVIN 1130 (20% in xylene) 2.4
TINUVIN 292 (20% in xylene) 1.2
DBDTL solution (2% in solvent C-IX) 0.6
BYK 358 0.4
BYK306 0.2
SILANE A187 0.8
BYK 4509 3
HALOX 550WF 1.5
Butyl acetate 12
Total 100
*CAB 551-2= cellulose acetate butyrate (Mn= 30,000) marketed by EASTMAN Chemical Company
S OL- solution in solvents i.e., Butyl acetate and MIBK (methyl isobutyl ketone).
C-IX= Solvent naphtha

Modified acrylic polyol resin prepared in Example 1, hydroxy functional acrylic resin, epoxy resin and mixed xylene were dispensed into a mixer manually or by an Air Operated Dispenser (AOD) pump and mixed at 100 rpm for 15-20 minutes.

Then, the raw materials CAB 551-2, TINUVIN 1130, TINUVIN 292, DBDTL solution, BYK 358, BYK 306, SILANE A 187, BYK 4509, and HALOX 550WF were added in sequence to the mixer.

The resulting solution was then mixed at 200-250 rpm at 30 minutes. The solution was checked for clarity as the solution should be clear with no suspension.

Then, butyl acetate was added to the solution to adjust the viscosity to 40-60 seconds on Ford viscosity cup B4 and stirred for 15 minutes until well-mixed.

Example 3: Coating a substrate with the polyurethane composition
The polymer composition of Example 2 was coated on different substrates such as metals (mild steel (MS), galvanized iron (GI), and Aluminum (Al)), glass, wood, tiles (Bison cement board) and adhesion strength of the polyurethane coating formed on the substrates was determined.

Procedure:
The surface of the substrate was cleaned to be free from any particulate matter.

The polymer composition and an isocyanate hardener (aliphatic HMDI) was mixed in a ratio of 4:1 by volume. A polyurethane (PU) thinner was added to adjust the viscosity of the mixture so that it was brushed easily on the surface of the substrate.

The mixture was evenly coated with a brush on the cleaned surface of the substrate and air dried to form a polyurethane coating.

Characterization
Characterization of the Polymer composition
The parameters such as viscosity, weight per liter (WPL), percent non-volatile matter (% NVM) was determined for polymer composition of Example 2 as per the present invention and compared with the conventional clear polyurethane composition as shown in Table 3 below. The conventional clear composition did not contain modified acrylic polyol resin, hydroxy functional acrylic resin and cellulose acetate butyrate.

Table 3
Sr. No Parameter Example 2 Conventional clear composition
1 Viscosity on Ford Cup (FC) B4 65 sec 73 sec
2 WPL 0.96 Kg/L 0.975 Kg/L
3 %NVM 48.40% 42%

The polymer composition as per the present invention had lower values for viscosity, weight per liter and non-volatile matter than the conventional clear composition.

Characterization of polyurethane film.
The thickness, adhesion and hardness of polyurethane film formed in Example 3 from the mixture of polymer composition of Example 2 and the isocyanate hardener was compared with the polyurethane film obtained using the conventional clear composition on the different substrates.

The adhesion test of the polyurethane film was performed as per ASTM-D3358.

Table 4 shows the results of the adhesion of polyurethane film on the substrates.

Sr. No Parameter Example 2 Conventional clear composition
1 Dry film thickness after application 35-40 µm 40-45 µm
2 Adhesion (should pass 5B, ASTM-D3358)
Metal substrates like MS, GI, Al Pass Pass
Glass Pass Fail
Wooden substrates Pass Fail
Tiles (Bison cement board) Pass Fail
3 Pencil hardness (should pass 2H) Pass Fail

The results showed that the polymer composition as per the present invention provided polyurethane coating having acceptable adhesion on all the tested substrates. While the conventional clear composition provided coating that only had acceptable adhesion on metal substrates. This shows that the polymer composition comprising modified acrylic polyol resin, hydroxyl functional acrylic resin and cellulose acetate butyrate provided a coating having superior adhesion on different types of substrate than conventional clear composition.

Also, the polymer composition provided a coating that had acceptable hardness while having a reduced thickness than that the film obtained with conventional clear composition.

The foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described to best explain the principles of the present invention and its practical application, to thereby enable others, skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated.
, Claims:We Claim:
1. A polymer composition comprising:
10%-40% by weight of a modified acrylic polyol resin;
20%-50% by weight of a hydroxyl functional acrylic resin; and
0.2%-2% by weight of cellulose acetate butyrate.

2. The polymer composition as claimed in claim 1, wherein molecular weight (Mn) of cellulose acetate butyrate is in a range of 20,000 to 50,000.

3. The polymer composition as claimed in claim 1 or 2, wherein cellulose acetate butyrate is in the form of a solution and wherein the solution is present in an amount of 1%-10% by weight of the polymer composition.

4. The polymer composition as claimed in any one of claims 1 to 3 comprising,
1%-5% by weight of a UV light absorber;
1%-5% by weight of a stabilizer;
0.1%-1% by weight of a catalyst;
0.1%-1% by weight of a levelling additive;
0.1%-0.5% by weight of a surfactant;
0.3%-1.5% by weight of a coupling agent;
1%-5% by weight of an adhesion promoter;
0.5%-2.5% by weight of a corrosion inhibitor;
0.5%-5% by weight of an epoxy resin; and
10%-40% by weight of a hydrocarbon solvent selected from aromatic hydrocarbon solvent, aliphatic hydrocarbon solvent or a combination thereof,
wherein the sum of the percentages of all the components present in the polymer composition is 100% by weight.

5. The polymer composition as claimed in any one of claims 1 to 4, wherein the composition comprises,
20%-30% by weight of the modified acrylic polyol resin;
30%-40% by weight of the hydroxyl functional acrylic resin;
3%-9% by weight of solution of cellulose acetate butyrate;
2%-4% by weight of the UV light absorber;
1%-3% by weight of the stabilizer;
0.3%-0.9% by weight of the catalyst;
0.2%-0.6% by weight of the levelling additive;
0.1%-0.5% by weight of the surfactant;
0.5%-1.0% by weight of the coupling agent;
2%-4% by weight of the adhesion promoter;
1%-2% by weight of the corrosion inhibitor;
1%-3% by weight of the epoxy resin;
10%-15% by weight of the aromatic hydrocarbon solvent; and
10%-15% by weight of the aliphatic hydrocarbon solvent,
wherein the sum of the percentages of all the components present in the polymer composition is 100% by weight.

6. The polymer composition as claimed in claim 4 or 5 wherein,
the UV light absorber is hydroxyphenyl benzotriazole;
the stabilizer is a mixture of bis (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) sebacate and methyl 1, 2, 2, 6, 6- pentamethyl-4-piperidyl sebacate;
the catalyst is di-butyl tin dilaurate;
the levelling additive is polyacrylate copolymer;
the surfactant is polyether-modified polydimethylsiloxane;
the coupling agent is epoxy functional silane;
the adhesion promoter is a salt of a polymer with acidic groups;
the corrosion inhibitor is a water free liquid organic-inorganic sol-gel;
the epoxy resin is type-1 epoxy resin;
the aromatic hydrocarbon solvent is mixed xylene; and
the aliphatic hydrocarbon solvent is butyl acetate.

7. A polymer composition comprising:
a modified acrylic polyol resin;
a hydroxyl functional acrylic resin; and
cellulose acetate butyrate.

8. A process for preparation of a polymer composition, the process comprising;
blending a modified acrylic polyol resin, and a hydroxyl functional acrylic resin to form a mix; and
adding cellulose acetate butyrate to form the polymer composition.

9. A process for preparation of a polymer composition as claimed in claim 4 or 5, the process comprising:
mixing a modified acrylic polyol resin, a hydroxyl functional acrylic resin, an epoxy resin and an aromatic solvent to form a solution;
adding cellulose acetate butyrate, a UV light absorber, a stabilizer, a catalyst, a levelling additive, a surfactant, a coupling agent, an adhesion promoter, and a corrosion inhibitor to form a clear solution; and
adding an aliphatic hydrocarbon solvent to the clear solution.

10. A two component (2K) polyurethane composition kit comprising,
a polymer composition as claimed in any one of claims 1-7; and
an isocyanate hardener;

11. The two component (2K) polyurethane composition kit, as claimed in claim 10, wherein the isocyanate is selected from isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HMDI) or a combination thereof.

12. A process for coating a substrate, the process comprising,
providing a two component (2K) polyurethane composition kit as claimed in claim 10 or 11;
mixing the polymer composition with the isocyanate hardener to form a coating mixture;
coating the substrate with the coating mixture.

13. The process as claimed in claim 12, comprising drying the coated substrate to form a polyurethane coating.

14. The process as claimed in claim 13, wherein the polyurethane coating comprises a linkage of Formula I,

-R-COO-NH-COONHR’- (Formula I)
where,
R is -(CH2)6-; and
R’ is -CH2-.

15. The process as claimed in claim 12, wherein the substrate is selected from glass, wood, sheet metal, fiber-reinforced polymer (FRP) or floor/tiles.

16. A process for preparation of a modified acrylic polyol resin as claimed in claim 1, the process comprising:
providing a reactor containing a hydrocarbon solvent;
preparing a monomer mix by mixing an acrylic acid based monomer, a reactive diluent, 2-hydroxyethyl methacrylate phosphate, a salt of acrylic acid, and an unsaturated carboxylic acid;
adding an initiator to the monomer mix;
adding the monomer mix containing the initiator to the reactor;
adding a chaser to the reactor; and
heating the reactor at a temperature in a range of 132°C-135°C to form the modified acrylic polyol resin.

17. The process as claimed in claim 16, wherein the initiator is added to the monomer mix prior to addition of the monomer mix to the reactor.

18. The process as claimed in claim 16 or 17, wherein
the hydrocarbon solvent in the reactor is heated to a temperature in a range of 132°C-135°C;
adding the monomer mix containing the initiation to the reactor over a period of 180 minutes and maintaining the temperature range of 132°C-135°C; and
adding the chaser to the reactor for a period of 30 minutes.

19. The process as claimed in any one of claims 16 to 18, wherein the acrylic acid based monomer is added in a range of 10%-20% by weight, the reactive diluent is added in a range of 15%-25% by weight, 2-hydroxyethyl methacrylate phosphate is added in a range of 10%-20% by weight, the salt of acrylic acid is added in a range of 15-25% by weight, the unsaturated carboxylic acid is added in an amount of up to 1% by weight, and initiator and chaser is added in an amount of up to 10% by weight.

20. The process as claimed in claim 16, wherein the acrylic acid based monomer is methyl methacrylate, the reactive diluent is styrene, the salt of acrylic acid is butyl acrylate, the unsaturated carboxylic acid is acrylic acid, the initiator and chaser is tertiary butyl per benzoate and the hydrocarbon solvent is an aromatic hydrocarbon solvent.

21. The process as claimed in claim any one of claims 16, wherein optionally mixed xylene is added to the reactor after formation of the modified acrylic polyol resin.

Dated this 30th day of August 2022

FOR PPG ASIAN PAINTS PRIVATE LIMITED
By their Agent

(ANSHUL SUNILKUMAR SAURASTRI) (IN/PA 3086)
KRISHNA & SAURASTRI ASSOCIATES LLP