Claims:We Claim:

1. Hybrid polyols comprising graft copolymerization product of:
(A) oil-modified polyester and/oralkydpolyols having polymerizable unsaturation, including unsaturation from an unsaturated polyacid/anhydride grafted and/or esterified to said oil-modified polyester and/or alkydpolyoland,
(B) polymerizable acrylic and/or vinylic monomers;
said graft copolymerizationproducthaving hydroxyl value 50-80 mg KOH/g or hydroxyl content in the range of 1.5 to 6.5% of said hybrid polyols and Gardner color value below 2 advantageously adapted for curing with isocyantes to provide for coatings with non-yellowing/good weathering performances.

2. Thehybrid polyols as claimed in claim 1 wherein said graft copolymers having said hydroxyl value 50-80 mg KOH/g is a copolymer of
15 to 22 wt% preferably 19.75 wt.% of saidoil modified polyester and/oralkyd polyol having polymerizableunsaturation and hydroxyl value in the range from 195 to 325 mg KOH/g preferably 240-290 mg KOH/g or hydroxyl content of 6-10% and acid value below 10 mg KOH/g and oil length of 21-44 wt.%; and;
34 to 54 wt% preferably 50 wt% of said polymerizable acrylic and/or vinylic monomers including styrene but free of any hydroxyl functional acrylic/vinylic monomer.
3. The hybrid polyols as claimed in claims 1 or 2 wherein said oil modified polyester and/or alkyd polyolhaving polymerizableunsaturation,is a condensation product of Soya oil fatty acid (SOFA), polyols selected from trimethylolpropane, pentaerythritol and glycerol& acid anhydridesinvolving a combination of both aromatic and aliphatic anhydride, and includes condensation product of unsaturated fatty acids/ polyols/ unsaturated acid anhydrides
wherein said oil modified polyester and/oralkyd polyolhaving polymerizable unsaturation,is based on ingredients comprising 21-26 wt.% Phthalic Anhydride, 1-3.5 wt.% Maleic Anhydride, 18-20 wt% Pentaerythritol, 12-14.5 wt% Glycerol, 35-41.5 wt.% SOFA.
4. The hybrid polyols as claimed in claim 3 wherein said oil modified polyesterand/or alkyd polyolhaving polymerizableunsaturation,is based on ingredients comprising 20-25 wt.% Phthalic Anhydride, 3-4 wt.% Maleic Anhydride, 10-14 wt% Pentaerythritol, 6-11 wt% trimethylolpropane, 9-17 wt% Glycerol, 39-41.5 wt.% SOFA.

5. The hybrid polyols as claimed in claims 1-4 wherein said oil modified polyesterand/or alkyd polyolhaving olefinic and/or vinylic unsaturation,is achieved with clear resin constitution at solids content of 93-95% and is dilutable up to 74-75% solids with cellosolve acetatewith clear resin constitution.

6. The hybrid polyols as claimed in claims 1-5 wherein said graft copolymers of oil modified polyesterand/or alkydpolyolhaving polymerizableunsaturation,and polymerizable acrylic and/or vinylic monomers are curable with isocyantes in the ratio of 75: 25 wt.% providing for coatings with non-yellowing/good weathering performances.

7. The hybrid polyols as claimed in claims 1-6 wherein said polymerizable acrylic and/or vinylic monomers include preferably butyl acrylate, vinyl monomers includes preferably styrene and said isocyantes include preferably Desmodur® N 75 BA.

8.A process for the preparation of hybrid polyols as claimed in claims 1-7 comprising the steps of:
providing oil modified polyesterand/or alkyd polyol resinhaving polymerizable unsaturation, and reacting with said polymerizable acrylic and/or vinylic monomers free of hydroxyl functional monomers or combination thereof in the presence of catalyst by free radical polymerization to obtain therefrom said hybrid polyol having hydroxyl value 50-80 mg KOH/g or hydroxyl content in the range of 1.5 to 6.5% of said hybrid polyols.

9. The process for the preparation of hybrid polyols as claimed in claim 8 wherein said

15 to 22 wt.% preferably 19.75 wt.% of said oil modified polyesterand/or alkyd polyolhaving polymerizableunsaturation and hydroxyl value in the range from 195 to 325 mg KOH/g preferably 240-290 mg KOH/g or hydroxyl content of 6-10% and acid value below 10 mg KOH/g is employed for free radical polymerization with 34 to 54 wt% preferably 50 wt.% of said polymerizable acrylate and/or vinylic monomers including styrene free of any hydroxyl functional monomer and preferably 20 wt.% of styrene in presence of catalysts including preferably tertiary butyl per benzoate to obtain therefrom said hybrid polyol having said hydroxyl value 50-80 mg KOH/g.

10. The process for the preparation of hybrid polyols as claimed in claims 8-9 wherein said free radical polymerization to generate said hybrid polyols involve steps of
(a) charging said oil modified polyesterand/or alkyd polyolhaving polymerizableunsaturation,and mix-xylene/MPA in the reactor with stirring;
(b) raising the temperature of the batch to 128-132 °C and continuing for 5-10 minutes;
(c) adding polymerizable monomers as premixturecomprising styrene, butyl acrylate and catalyst, preferably tertiary butyl per benzoate, from monomers vessel through metering pump at a controlled rate over a time period of 120 minutes sustaining temperature 128-132 °C throughout monomer addition;
(d) continuing further for about 60 more minutes at 128-132°C temperature after addition of remaining initiator;
to yield therefrom said copolymers as clear liquid with Gardner color value below 2 possessing non yellowing / good weathering performances.

11. The process for the preparation of hybrid polyols as claimed in claims 8-10 wherein said oil modified polyesterand/or alkyd polyol resinhaving polymerizable unsaturation, is prepared by the following steps

I. heating mixture of ingredients comprising Phthalic Anhydride, Pentaerythritol, SOFA, Maleic Anhydride, Glycerol, optionally trimethylolpropane (TMP), solvent and catalyst preferably hypophosphoric acid in a reactor equipped with temperature controller, heating arrangement, inert gas purger, overhead stirrer and reflux condenser to 180 °C
II. raising the temperature of the mixture slowly to 240 °C till acid value reaches below 10 mg KOH/g with a solid content of 93-95%;
III. Cooling the reaction mass to 130-140°C followed by dilution with solvent to make solid content ~74%.

Dated this the 10thday of June, 2021 Anjan Sen
Of Anjan Sen & Associates
(Applicants Agent)
IN/PA-199

, Description:
Field of the Invention
The present invention provides for multiple functional oil-modified polyester and/or alkyd polyols having polymerizable unsaturationcomprising graft copolymers of saidoil-modifiedpolyester and/oralkyd polyol and polymerizable acrylic and/or vinylic monomersand coating compositions thereof adapted for non-yellowing performance/good weathering properties.
Background of the Invention
Alkyds are the reaction products of the esterification reaction between polyols, fatty acid(s) and polybasic acid(s). The typical esterification procedure involves charging these three components to a reaction vessel and reacting at a temperature of around 400-5000F.
The polybasic acids suitable for use in preparation of the alkyd resin constituent are aromatic, aliphatic and alicyclic saturated and polybasic acids, and include such acids as phthalic acid, adipic acid, isophthalic acid, terephthalic acid, maleic acid, trimellitic acid, tetrahydrophthalic acid, sebacic acid, napthalic acid, chlorendic acid, heptanedioic acid and succinic acid and anhydrides thereof. Preferred acids include phthalic, isophthalic and maleic acids and anhydrides.
Polyhydric alcohol components are those which can react with the carboxyl groups of polybasic acids in an esterification reaction and which have at least two hydroxyl groups. Examples of suitable alcohols include ethylene glycol, diethylene glycol, glycerin, pentaerythritol, trimethylol ethane, trimethylol propane, neopentyl glycol, propylene glycol, sorbitol, dipropylene glycol, 1,6-hexanediol, 1,3-butylene glycol, dipentaerythritol and triethylene glycol. The preferred polyols are trimethanol ethane, pentaerythritol, neopentyl glycol and propylene glycol.
Suitable fatty acids include linoleic acid, linolenic acid, oleic acid, eleosteric acid, and stearic acid. Generally, useful fatty acids have molecular weights in the range of about 140 to about 300.Fatty acids used in the manufacture of alkyds may be derived from biological oils. Oils commonly used in the manufacture of alkyds include tung oil, oiticica oil, dehydrated castor oil, fish oil, linseed oil, safflower oil, soya oil, tall oil acids, cottonseed oil and coconut oil. Particularly useful oils are soya oil and tall oil, which consist of mixtures of suitable fatty acids.
Oil length (OL) is a core concept in the area of alkyd. It normally refers to the oil portion of an alkyd expressed as a percentage of the final alkyd weight. For purpose of convenience the oil length is usually based on a charged weight instead of a final weight. Alkyd resins with less than 40wt% oil length are called short oil. Those that has 40wt%-60wt% OL are referred to as medium oil, and those with OL over 60wt% oil content are referred to as long oil.
Short oil-length alkyds are compatible in aromatic but not aliphatic solvents and usually used as baking primers and enamels offering high quality color and gloss retention, but slow drying and limited compatibility with low toxicity aliphatic solvent are the main drawbacks of this type of alkyds.
Medium oil-length alkydsare compatible in both aliphatic and aromatic solvent. The air-drying medium oil alkyd is commonly used as standard vehicle for industrial coating, like primers and undercoatings, anti-corrosion coatings.
Long oil-length alkyds are compatible in aliphatic solvent having better pigment dispersion, rheological properties, and storage stability than the other types, therefore they could be applied by brush and be used as exterior trim paints, wall paints, and metal maintenance paints.
Some relevant prior references are represented hereunder:
US3620989teaches a distinctive alkyd is made by reacting at a temperature below 350 F., an unsaturated dibasic acid or anhydride (e.g., maleic anhydride or fumaric acid) with an unsaturated fatty acid ester (e.g. safflower oil) that has been alcoholized with a polyol (e.g., ethylene glycol). This alkyd can then be emulsion copolymerized with various polymerizable monomers (e.g. vinyl acetate, styrene) to produce a high molecular weight polymer that is thermosetting and forms tough homogeneous films.

US3357936 discloses coating composition comprising the reaction product of (a) a vinylidene aromatic copolymer having more than 10 up to 20 weight percent of an a, ß-unsaturated cyclic anhydride and a number average molecular weight of less than 10,000 at least 90 percent of said copolymer having an anhydride component composition within a range of 5 percent by fractionation analysis, (b) a polyol and (c) a fatty acid in a proportion such that the hydroxyl to carboxyl ratio is from 0.6 to 1.6.
CN102807808 discloses a paint prepared by mixing 114-5 resin 80-120 with DCP 0.6-0.8, cobalt isooctanoate 0.04-0.07 and styrene 4-14 wt. part, stirring for >30 min, checking, and packaging, wherein the 114-5 resin was prepared by mixing dicyclopentadiene 48-58 with water 11-15 and maleic anhydride 30-38, heating at 120-130° for 2 h, adding soybean oil acid 31-39, glycerin 27-33, propylene glycol 5-9, phthalic anhydride 18-22, hydroquinone 0.01-0.02, and xylene 5-7, refluxing at 160° for 1h, 170° for 1 h, 180° for 1 h, and 190° for 1 h, heating to 200° until AR=20 mgKOH/g, vacuuming until AR=10 mgKOH/g to obtain mixt. A, mixing hydroquinone 0.1-0.2 with styrene 80-120 to obtain mixt. B, slowly adding A into B, and stirring at =75° for =120 min.

BR2010004087A2 teaches a process of obtaining unsaturated polyester resin, composition of unsaturated polyester resins and their respective uses wherein said process according to the advancement comprises the following steps:
first step: introduces one or more polyhydric alcohols. (c) at least one renewable source, i.e. vegetal or animal, one or more fatty acid (d) and optionally: one or more acids or anhydrides of saturated carboxylic acid (a) and / or one or more salts of potassium or calcium (g), and this mixture is heated in an inert atm. to temperatures less than 240° until reaching an acid no. below 30 mg KOH / g resin;
second step: the temperature of the mixture obtained in the first step is reduced below 240° and one or more acids or anhydrides of unsaturated dicarboxylic acids (b) can be added and / or one or more acids or anhydrides of satd. carboxylic acid (a) and / or one or more polyhydric alcohols.(c).
third step: the temp. of the reaction medium is kept below 205° until reaching an index acidity lower than 70 mg KOH / g resin:
fourth step: the temp. of the reaction medium is increased to a value below 220° until reaching an acid value below 80 mg KOH / g resin and viscosity below 80;
fifth step: the temperature inside the reactor can vary from 170 to 240° optionally adding one or more aromatic polyols (e);
sixth step: the temperature of the reaction medium is reduced to less than 200° for there to be introduced one or more monomers of aliphatic or aromatic hydrocarbons (f) and / or one or more aromatic polyols (e), the latter could introduce branching unsaturated containing. 1 to 6 carbon atoms;
seventh step: optional step, at a temperature below 170° can be added one or more monomers of aliphatic or aromatic hydrocarbons (f). Thus, a polyester resinwas obtained by this prior art from less than 30% orthophthalic acid, less than 20% maleic anhydride, 8-30% of propyleneglycol and glycerol, 7-24% soy oil, less than 500 ppm of hydroquinone, 70% styrene and 1000 ppm calcium carbonate.
EP0962507A1 discloses binder for coating composition obtainable as the reaction product of a carboxyl-terminated fatty acid ester with an ethylenically unsaturated carboxylic acid and an ethylenically unsaturated carboxylic acid ester. The carboxylic fatty acid ester is produced by reaction of an autoxidisable fatty acid and a polyol, with modification to introduce at least one terminal carboxyl group. The reaction is optionally effected in an organic solvent which is substantially removed at the end. The material is neutralized with a base to render it water-soluble. Thixotropy can be endowed by an amine/ (poly)isocyanate final reaction stage to prior neutralization. Thus covers a binder for a water-based coating composition, the binder being obtainable as the product of a reaction mixture comprising:(a) a carboxyl-terminated fatty acid ester obtainable as the reaction product of an autoxidisable fatty acid and a polyol followed by a reaction to attach a carboxyl group;(b) an ethylenically unsaturated carboxylic acid; and(c) an ester of an ethylenically unsaturated carboxylic acid.
JP55144013A teaches polyester casting compositions for electric insulators wherein the composition of 40-80 parts of unsaturated polyesters derived from polyols 50-65, unsaturated fatty acids 5-30, and 5-38:62-95 (equiv.) mixture of aromatic dicarboxylic acids and aliphatic dicarboxylic acids 20-40 equiv. %, 20-60 parts of unsaturated compd. b. =200°, and =500 wt.% (based on the polyester) of inorganic fillers are useful as castable materials for elec. insulators. Thus, a mixture of propylene glycol 5.5, ethylene glycol 1.2, soya fatty acid 2:0, maleic anhydride 3.4, and phthalic anhydride 0.6 equiv. with 0.1 g hydroquinone was heated at 140-210° to give copolymer (I). A composition of I 550, 2-hydroxyethyl methacrylate [868-77-9] 400, and trimethylolpropane trimethacrylate [3290-92-4] 50 parts was mixed with 0.5 wt.% Co octanoate and 1% MeCOEt peroxide, cast in contact with bolts and nuts, left 24 h at 25°, and heated 1 h at 80° to give a product having heat-shock resistance >5 cycles (1 h at 120°, 15 min at 25°, and 1 h at -30°).
US20030195292A1reveals waterborne acrylate-functionalized alkyd coating compositions that are waterborne acrylate-functionalized alkyd coating compositions, which includes an acrylate-functionalized alkyd resin, at least one drier, and water. The acrylate-functionalized alkyd resin comprises the reaction product of (i) a hydroxy functional alkyd resin, (ii) an acid anhydride, and (iii) a glycidyl acrylate. Methods of preparing waterborne acrylate-functionalized alkyd coating compositions are also disclosed. Also covered is a waterborne acrylate-functionalized alkyd coating composition, comprising:(I) an acrylate-functionalized alkyd resin comprising the reaction product of: (a) about 79 to about 95 wt % of an alkyd resin having an acid number of from 0 to about 100 mg KOH/g;(b) about 2 to about 8 wt % of an acid anhydride; and(c) about 3 to about 13 wt % of a glycidyl acrylate, wherein the glycidyl moiety of the glycidyl acrylate is the reactive moiety and the reaction product contains reactive acrylate moieties, and wherein the weight percents are based on the total weight of (a), (b) and (c); (II) at least one drier; and(III) water. Said waterborne acrylate-functionalized alkyd coating composition involves said alkyd resin comprising the reaction product of: (i) 0 to about 30 mol % of a diol;(ii) about 10 to about 40 mol % of a polyol;(iii) about 20 to about 40 mol % of a polyacid;(iv) 0 to about 10 mol % of a monofunctional acid; and(v) about 10 to about 50 mol % of a fatty acid, fatty ester or naturally occurring oil, wherein the mole percents are based on the total moles of (i), (ii), (iii), (iv) and (v).
US20190055411teaches acrylic-modified alkyd resin and coating material for priming for thin inorganic film wherein provided are a coating material that is for undercoating for a thin inorganic film, has excellent adhesiveness to various base materials, and produces no appearance change or no peeling off even under high-temperature conditions, and an acrylic-modified alkyd resin as a raw material for such a coating material. The acrylic-modified alkyd resin includes a copolymer including as essential components: an alkyd resin (A) having an unsaturated bond in a molecular structure; and a polymerizable monomer (B) having an unsaturated bond in a molecular structure. Also provided are a curable composition, a coating material for undercoating for a thin inorganic film, and a molded body including an undercoat layer including the coating material for undercoating for a thin inorganic film. Thus teaches an acrylic-modified alkyd resin comprising a copolymer comprising as essential components: an alkyd resin (A) having an unsaturated bond in a molecular structure; and a polymerizable monomer (B) having an unsaturated bond in a molecular structure.
Edja F. AssanvoShashi and D.Baruah (Synthesis and properties of Ricinodendron heudelotii oil based hybrid alkyd–acrylate latexes via miniemulsion polymerization Progress in Organic CoatingsVolume 86, September 2015, Pages 25-32) disclosed synthesis of Ricinodendron heudelotii (R. heudelotii) oil-based novel alkyd–acrylate hybrid latexes as waterborne environmental friendly binder for coating systems. Long oil length alkyd resins were synthesized by two-stage alcoholysis–polyesterification reaction with variation of phthalic anhydride (PA) and maleic anhydride (MAH) proportion and further polymerized with methyl methacrylate (MMA) and butyl acrylate (BA) via miniemulsion polymerization. It was found that increasing the proportion of MAH in the alkyd resin enhanced monomer conversion and total solid content of the hybrid latex. It was also shown that the increase in MAH content in the alkyd moiety has a significant effect on the improved performance properties of hybrid latexes as well as latex films including, fast drying time at room temperature, highly crosslinked network, improved mechanical characteristics before and after UV exposure, better shore A hardness and hydrophobic water repellency contact angle.
Mongi ElrebiiAymanBen Mabrouk and Sami Boufi (Synthesis and properties of hybrid alkyd–acrylic dispersions and their use in VOC-free waterborne coatings Progress in Organic CoatingsVolume 77, Issue 4, April 2014, Pages 757-764) reported hybrid waterborne alkyd–acrylic dispersions with solid content of 40%, free from any surfactant and exempt of any organic solvent, were successfully synthesized by a melt co-condensation reaction between an acrylic prepolymer bearing carboxylic groups and a long-oil alkyd resin. Spontaneous emulsification of the ensuing hybrid resin was achieved by the addition of an aqueous ammonia solution that neutralized the carboxylic functions. The key role of the carboxylic groups on the stabilization process and on the storage stability of the dispersion was assessed and it was shown that the insertion of anhydride moieties within the acrylic prepolymer ensured the efficient coupling between the acrylic and the alkyd resin and prevented the phase separation. These dispersions are easy to implement and might be used to prepare high quality zero VOC coatings in terms of drying time, stability and gloss. The most stable dispersion was also used in the formulation of air-drying waterborne lacquers and their coating properties were evaluated.
C.OAkintayo and K. OAdebowale (Synthesis and characterization of acrylated Albizia benth medium oil alkydsProgress in Organic CoatingsVolume 50, Issue 4, September 2004, Pages 207-212 https://doi.org/10.1016 /j.porgcoat.2003.09.017) investigatedthe modification of Albizia benth medium oil alkyd by acrylation for improving their properties. The results revealed that acid functional acrylic copolymers containing maleic anhydride as a functional co-monomer can successfully be used to modify alkyd resins yielding acrylated resins with better drying, flexibility, scratch hardness, impact resistance and chemical resistance properties.
However, there existsscope for modification of alkyds with such copolymers beyond which certain film properties are adversely affected.Numerous reports on the similar concept are there for developing coating formulation. But there is a need to explore different polyol resins and constitution/ composition thereof that would be adapted for coatings with durable finish and more importantly with non-yellowing/good weathering properties.

Objectives of the invention
The primary objective of the present invention is to provide for hybrid polyol and coating compositions thereof comprising selective hybrid polyol as a clear liquid resinhaving gardner color value below 2, adapted for non-yellowing/ good weathering performance.
Another objective of the present invention is to provide for said hybrid polyol involving acrylates devoid of hydroxyl groups and free of hydroxy-Ethyl Acrylate (HEA), Hydroxy-Ethyl Methyl Acrylate (HEMA), Hydroxy-Propyl Acrylate (HPA), Hydroxy-Propyl Methacrylate (HPMA) and styreneas monomers.
Yet another objective of the present invention is to provide said hybrid polyol which is a graft copolymer of precursor unsaturated polyester polyol and hydroxyl free acrylate monomers.
Another objective of the present invention is to provide said unsaturated polyester/alkydpolyol as precursor to said hybrid that would be obtained of esterification reaction involving multifunctional fatty acid(soya oil fatty acid),phthalic anhydride as acid sources and Maleic anhydride as a multifunctional (acid and unsaturation source) Trimethylolpropane,Glycerol, and pentaerythritol as alcohol sources.
Yet another objective of the present invention is to provide for said hybrid polyol by graft copolymerization of polymerizable monomers and said polyester/alkyd polyol in presence of free radical catalyst.
Another preferred objective of the present invention is to provide coating films having superior mechanical properties including lesser drying time and non-yellowing/ good weatheringproperties involving curing of said hybrid polyolswith isocyanates.
Another objective of the present invention is to provide for said hybrid polyol following a method which could be accomplished either in different reactors or in a single reactor.

Summary of the invention

In the primary aspect the invention is directed to provide Hybrid polyols comprising graft copolymerization product of:
(A) oil-modified polyester and/or alkydpolyols having polymerizable unsaturation, including unsaturation from an unsaturated polyacid/anhydride grafted and/or esterified to said oil-modified polyester and/or alkydpolyoland,
(B) polymerizable acrylic and/or vinylic monomers;
said graft copolymerization product having hydroxyl value 50-80 mg KOH/g or hydroxyl content in the range of 1.5 to 6.5% of said hybrid polyols and Gardner color value below 2 advantageously adapted for curing with isocyantes to provide for coatings with non-yellowing/good weathering performances.

Another aspect of the present invention is directed to provide said graft copolymers having said hydroxyl value 50-80 mg KOH/g is a copolymer of
15 to 22 wt% preferably 19.75 wt.% of said oil modified polyester and/or alkyd polyol having polymerizableunsaturation and hydroxyl value in the range from 195 to 325 mg KOH/g preferably 240-290 mg KOH/g or hydroxyl content of 6-10% and acid value below 10 mg KOH/g and oil length of 21-44 wt.%; and;
34 to 54 wt% preferably 50 wt% of said polymerizable acrylic and/or vinylic monomers including styrene but free of any hydroxyl functional acrylic/vinylic monomer.

Another aspect of the present invention is directed to provide said oil modified polyester and/or alkyd polyol having polymerizableunsaturation, is a condensation product of Soya oil fatty acid (SOFA), polyols selected from trimethylolpropane, pentaerythritol and glycerol& acid anhydridesinvolving a combination of both aromatic and aliphatic anhydride, and includes condensation product of unsaturated fatty acids/ polyols/ unsaturated acid anhydrides
wherein said oil modified polyester and/oralkyd polyol having polymerizable unsaturation, is based on ingredients comprising 21-26 wt.% Phthalic Anhydride, 1-3.5 wt.% Maleic Anhydride, 18-20 wt% Pentaerythritol, 12-14.5 wt% Glycerol, 35-41.5 wt.% SOFA.

Yet another aspect of the present invention is directed to provide said oil modified polyesterand/or alkyd polyol having polymerizableunsaturation, is based on ingredients comprising 20-25 wt.% Phthalic Anhydride, 3-4 wt.% Maleic Anhydride, 10-14 wt% Pentaerythritol, 6-11 wt% trimethylolpropane, 9-17 wt% Glycerol, 39-41.5 wt.% SOFA.

Still another aspect of the present invention is directed to provide saidoil modified polyesterand/or alkyd polyol having olefinic and/or vinylic unsaturation, is achieved with clear resin constitution at solids content of 93-95% and is dilutable up to 74-75% solids with cellosolve acetatewith clear resin constitution.

Further aspect of the present invention is directed to provide saidgraft copolymers of oil modified polyesterand/or alkydpolyol having polymerizableunsaturation,and polymerizable acrylic and/or vinylic monomers curable with isocyantes in the ratio of 75: 25 wt.% providing for coatings with non-yellowing/good weathering performances.

Still further aspect of the present invention is directed to provide saidhybrid polyols wherein said polymerizable acrylic and/ or vinylic monomers include preferably butyl acrylate, vinyl monomers includes preferably styrene and said isocyantes include preferably Desmodur® N 75 BA.
Another preferred aspect of the present invention is directed to provide aprocess for the preparation of hybrid polyols comprising the steps of:
providing oil modified polyesterand/or alkyd polyol resin having polymerizable unsaturation, and reacting with said polymerizable acrylic and/or vinylic monomers free of hydroxyl functional monomers or combination thereof in the presence of catalyst by free radical polymerization to obtain therefrom said hybrid polyol having hydroxyl value 50-80 mg KOH/g or hydroxyl content in the range of 1.5 to 6.5% of said hybrid polyols.

Another aspect of the present invention is directed to provide saidprocesswherein said 15 to 22 wt.% preferably 19.75 wt.% of said oil modified polyesterand/or alkyd polyol having polymerizableunsaturation and hydroxyl value in the range from 195 to 325 mg KOH/g preferably 240-290 mg KOH/g or hydroxyl content of 6-10% and acid value below 10 mg KOH/g is employed for free radical polymerization with 34 to 54 wt% preferably 50 wt.% of said polymerizable acrylate and/or vinylic monomers including styrene free of any hydroxyl functional monomer and preferably 20 wt.% of styrene in presence of catalysts including preferably tertiary butyl per benzoate to obtain therefrom said hybrid polyol having said hydroxyl value 50-80 mg KOH/g.

Still another aspect of the present invention is directed to provide saidprocess wherein said free radical polymerization to generate said hybrid polyols involve steps of
(a) charging said oil modified polyesterand/or alkyd polyol having polymerizableunsaturation, and mix-xylene/MPA in the reactor with stirring;
(b) raising the temperature of the batch to 128-132 °C and continuing for 5-10 minutes;
(c) adding polymerizable monomers as premixture comprising styrene, butyl acrylate and catalyst, preferably tertiary butyl per benzoate, from monomers vessel through metering pump at a controlled rate over a time period of 120 minutes sustaining temperature 128-132 °C throughout monomer addition;
(d) continuing further for about 60 more minutes at 128-132°C temperature after addition of remaining initiator;
to yield therefrom said copolymers as clear liquid with gardner color value below 2 possessing non yellowing / good weathering performances.

Still further aspect of the present invention is directed to provide said process wherein said oil modified polyesterand/or alkyd polyol resin havingpolymerizable unsaturation, is prepared by the following steps

I. heating mixture of ingredients comprising Phthalic Anhydride, Pentaerythritol, SOFA, Maleic Anhydride, Glycerol, optionally trimethylolpropane (TMP), solvent and catalyst preferably hypophosphoric acid in a reactor equipped with temperature controller, heating arrangement, inert gas purger, overhead stirrer and reflux condenser to 180 °C
II. raising the temperature of the mixture slowly to 240 °C till acid value reaches below 10 mg KOH/g with a solid content of 93-95%;
III. Cooling the reaction mass to 130-140°C followed by dilution with solvent to make solid content ~74%.
II. raising the temperature of the mixture slowly to 240 °C till acid value reaches below 10 mg KOH/g with a solid content of 93-95%;
III. Cooling the reaction mass to 130-140°C followed by dilution with solvent to make solid content ~74%.

Detailed description of the invention
The present invention provides for selective hybrid polyol having gardner color value below 2 and fortified with non-yellowing/ good weathering performanceas graft copolymers and coating compositions thereof, comprising a reaction product of precursor multifunctional oil-modified polyester and/or alkyd polyols having olefinic and/or vinylic unsaturationand polymerizable monomers, said polymerizable monomers includes acrylates devoid of hydroxyl groups i.e.being free of hydroxy-Ethyl Acrylate (HEA), Hydroxy-Ethyl Methyl Acrylate (HEMA), Hydroxy-Propyl Acrylate (HPA), Hydroxy-Propyl Methacrylate (HPMA) etc. and styrene or derivatives or a mixture thereof.
Preferably, said precursoroil-modified polyester and/or alkyd polyols having polymerizable unsaturationconstituting said polymerizable hybrid polyol is obtained of esterification reaction by involving multifunctional fatty acid (preferably soy fatty acid), phthalic anhydride as acid sources and maleic anhydride as a multifunctional source (acid and unsaturation) together with trimethylolpropane, glycerol, and pentaerythritol, as alcohol sources.
Said hybrid polyol graft copolymers are synthesized throughpolymerization ofprecursor oil-modified polyester and/oralkyd polyols having polymerizable unsaturationwith saidpolymerizable monomers in the presence of a free radical catalyst. The selective copolymers thus obtained in accordance with the present inventionare clear liquids having gardner color value below 2 and which when cured with selective isocyanates furnish coating with excellent non-yellowing/ good weathering performance.
The various selective weight % of multiple functional monomer combinations (maleic anhydride and SOFA) with glycerol, pentaerythritol and TMPas the alcohol sourceprovide for precursor oil-modified polyester and/or alkyd polyol with hydroxyl content below 10 mg KOH/g – which when constitutes the hybrid polyols including acrylic and vinylic monomers exhibitsdifferent viscosity and hydroxyl content of 1.5 to 6.5%of said hybrid polyols, which is 50-80 mg KOH/g.
Finally curable coating formulationsare obtained by using isocyanate and these coating films possess a wide array of different curing rates, mechanical properties and non-yellowing/ good weathering properties.
1) First the multifunctionaloil-modified polyester and/or alkyd polyols having polymerizable unsaturationare formed by reacting multifunctional monomer i.e. Maleic anhydride 1 to 5%, Soya fatty acid SOFA (soya fatty acid) 16-60%and phthalic anhydride 20 to 26% of polyester polyol withselect ratios of Trimethylolpropane,Glycerol, and Pentaerythritol to get clear liquids having hydroxyl content 6-10 mg KOH/g;
2) Acrylation and /or vinylation of above synthesized multifunctionaloil-modified polyester and/or alkyd polyols having olefinic and/or vinylic unsaturationwith combination of acrylate and vinyl monomers to get hybrid polyols having hydroxyl content 1.5 to 6.5%, which is 50-80 mg KOH/g, with different viscosities.
3) Different curing rate and non-yellowing/ good weathering properties attained thereof when cured with selective isocyanates to provide for coatings.

EXAMPLES

Stage 1
Synthesis and properties of multiple functionaloil-modified polyester and/or alkyd polyols having olefinic and/or vinylic unsaturationin accordance with the invention.
The multiple functional polyester and/or alkyd polyols were synthesized by heating a mixture of phthalic anhydride, pentaerythritol, SOFA, maleic anhydride, glycerol, mix xylenein a reactor fitted with reflux condenser and inert gas purger until acid value reaches below 10 mg KOH/gm. Subsequently the reaction mass was cooled and diluted with xylene/cellosolve acetate solvent to yield a solution having 74-75% solid.

Table 1: Reagents and chemicals used foroil-modified polyester and/or alkyd polyols having olefinic and/or vinylic unsaturation (1A-1H) synthesis

Examples (1A) (1B) (1C) (1D) (1E) (1F) (1G) (1H)
PHTHALIC ANHYDRIDE 23.5 23.5 21.5 23.5 24.5 40 25 23.68
Pentaerythritol 18.5 10 14 18.5 19.5 19 12 18.42
SOFA 41 39.5 41 38 38 19.5 39.5 40.78
Maleic Anhydride 3 3.5 3 5 4 3.5 3.5 2.63
Glycerol 14 16 10 15 14 18 20 14.47
TMP 0 7.5 10.5 0 0 0 0
Total 100 100 100 100 100 100 100 100
Mix xylene 5 5 5 5 5 5 5
Acid value Below 10 Below 10 Below 10 Below 10 Below 10 Below 20 Below 10
Hydroxyl value mg KOH/g 270-280 270-280 270-280 270-280 270-280 270-280 270-280
Solid content 93-95% Clear Clear Clear Hazy Clear gelled clear
Dilution with mix xylene solvent to make solid content 74-75% Hazy appearances after two days Hazy appearance with in 24 hr Hazy appearance after 2 days - Hazy appearance after 2 days Hazy appearance after 7 days
Dilution with cellosolve acetate solvent to make solid content 74-75% Clear Clear Clear - clear clear

Polyesterand/oralkyd polyols (1A-1C, 1E and 1G) at high levels of solid content were not only clear but could also tolerate dilution with solvents. Dilution with xylene was stable even after 7 days (1G)and others (1A-1C, 1E, 1G) were clear when diluted with cellosolve acetate solvent.
Example-1

Table 2: Chemicals and reagents for the preparation of selective oil-modified polyester and/or alkyd polyols having olefinic and/or vinylic unsaturationprecursor.

Sr. No. Raw materials Parts by weight
(1H) Parts by weight when totaled to 100 (1H)
1 PHTHALIC ANHYDRIDE 18 23.68
2 Pentaerythritol 14 18.42
3 SOFA 31 40.78
4 Maleic Anhydride 2 2.63
5 Glycerol 11 14.47
Total 76 100
Mix xylene 3.95
6 Hypophosphoric acid 0.05
7 Cellosolve acetate 20

Reaction vessel,equipped with temperature controller, heating arrangement, inert gas purger preferably nitrogen purger, overhead stirrer and reflux condenser, is charged with Phthalic Anhydride, Pentaerythritol, SOFA, Maleic Anhydride, Glycerol, hypophosphoric acid and Mix xylene with the preferred quantities as mentioned in Table-2.
Heating the reaction mixture to 180 °C followed by slow raise of the reaction temperature to 240°C till acid value reaches below 10 mg KOH/g;
Cooling the reaction mass to 130-140°C;
Diluting of polyester and/or alkyd polyol (1A) with xylene/ cellosolve acetate solvent to make solid content 74%.
It is noteworthy to mention that the reaction mass having acid value below 10 mg KOH/g is clear with a solid content of 93-95% which upon dilution with cellosolve acetate to a mixture with 74-75% solid content is clear too.

Stage 2: Synthesis of hybrid polyols
For synthesis of the hybrid polyols the above synthesized polyols (OMP-Oil Modified Polyols) and Mix-xylene/MPA were charged in the reactor with stirring. After raising the batch temperature to 128 to 132 deg C Premix of acrylate and vinyl monomer were added at a controlled rate. Remaining initiator was added after completion of monomer addition and the reaction continued further at the same temperature. After the reaction, the reaction mass was diluted to specific solid content.
Table-3 Preparation of hybrid polyol involving different polyester and/oralkyd polyols
OIL MODIFIED POLYOLS 1D 1E 1A 1A* X1 X2
Stage 1 PHTHALIC ANHYDRIDE 23.5 24.5 23.5 23.5 25 17.69
Pentaerythritol 18.5 19.5 18.5 18.5 18.5 14.23
SOFA 38 38 41 41 41 34.19
Maleic Anhydride 5 4 3 3 1.5 0
Glycerol 15 14 14 14 14 10.76
Mix xylene 5 5 5 5 14.23
Acid value Below 10 Below 10 Below 10 Below 10 Below 10 Below 10
Hydroxyl value mg KOH/g 270-280 270-280 270-280 270-280 270-280 270-280
Solid content 93-95% 94% 94% 94% 94% 94% 94%
Dilution with cellosolve acetate solvent to make solid content 74-75%

Stage 2 (Acrylations and/or vinylations) Stage 1 polyol quantity (74-75% solid) as it comes out as the product from stage 1, taken as solid 25.4 22.66 26.34 26.34 25.53 22.54
Butyl acrylate 29.5 29.8 20 29.5 20.8 29.4
Styrene 20 22 29.5 20 30 22.8
O-xylene 12.9 19.34 17.96 17.96 17.47 19.06
Methoxy propyl acetate 10 4 4 4 4 4
TBPB 2.2 2.2 2.2 2.2 2.2 2.2
% Solid content 70% 70% 70% 70% 70% 70%
viscosity Gel (not measurable) Z5-Z6 Z3-Z4 Z3-Z4 Z3-Z4 Y-Z
Hydroxyl value 60-80 60-80 60-80 60-80 60-80 60-80
Surface Drying time - 65 MIN 60 min 90 min 60 MIN 12 hrs
O-XYLENE rubs after 24 hrs - 10 18 14 10 3
% Gloss Retention, QUV B Resistance
ASTM G 53(500 hrs) - Due to high viscosity not measured 55% 76% 50% Not measured
1A and 1A* - stage I is identical for both of them but stage-2 is different.

Hybrid polyol graft copolymers having hydroxyl value in the range of 60-80 are synthesized through polymerization of as synthesized oil-modified polyester and/oralkyd polyols having polymerizable unsaturationwith different combinations of butyl-acrylate and styrene monomers maintaining the quantity of the said monomers at around 50% in the presence of a free radical catalyst. After the reaction, the reaction mass is diluted upto around 70% solid content.
Although all the Stage-2 reactionsare done with clear multiple functional oil-modified polyester and/or alkyd polyols having olefinic and/or vinylic unsaturationobtained from Stage-1 of the manufacture but they possess different viscosities. The viscosity at room temperaturevaried from gel formation (thus not measureable), Y-Z to Z5-Z6 that reveals the thermoplastic characteristics of the hybrid polyol. Wherein the preferable clear hybrid polymer mixture is having Gardner color value below 2 and fortified with non-yellowing/good weathering performance.
The inherent difference among the clear hybrid polymers having Gardner color value below 2, is evidenced by the physical attributes of the final coating films obtained after curing with Desmodur® N 75 BA having %NCO 16.5 with respect to surface drying time, O-xylene rubs after 24 hrs and % Gloss retention. X2 showed a drying time of 65 mins and O-xylene rubs after 24 hrs, 10, however % gloss retention could not be measured due to high application viscosity.
For 1E, 1A, X1 OMPs when passes to the acrylate and/or vinylichybrid, the drying time was within 60-90 minutes, O-xylene rub and % gloss retention after 500 hrs accelerated test under UV were 18, 14,10 and 55%, 76% and 50% respectively. Whereas the drying time for X2having no maleic anhydride was 12 hrs with O-xylene rub test of 3 and hence % gloss retention could not be measured.
[The wt.% data in Table-3 above should be read considering 70% solids generated as a product after stage 2 and hence to be multiplied with 0.7 to corroborate with the data under Tables 5-7.]
This is also evident from the examples that the ratio of SOFA and maleic anhydride has profound effect on the nature of the final propertiessuch as viscosity of the hybrid polymer as well as the films obtained from same after curingbecause in the process of synthesizing this oil modified polyesterand/or alkyd polyol the polymerizable double bond is coming from the ring-opening grafting of maleic anhydride to the oil-modified polyester and/or alkyd, before further reacting with the component (B) that is the polymerizable acrylic and/or vinylic monomers.
In fact, examples have shown that the grafting of maleic anhydride to the oil-modified polyester and/or alkyd is key to completion of the component (A). If maleic anhydride is not grafted and the double bonds of the oil are attempted to polymerize with the component (B), the resulting hybrid polyol remains non-drying even after the curing with isocyanate to deliver a final coating. (Table-3, X2). Thus, the grafting of maleic anhydride to the oil modified polyester and/or alkyd is the key to the technical advantage and inventive nature of this invention
Interestingly, the ratio of polymerizable monomers (styrene vs. butyl acrylate)also influences the character of the hybrid or more specifically the films obtained after curing.

Example 2
The hybrid polyol was synthesized according to the representative method as described below

Table-4: Reagents and chemicals used for hybrid polyol synthesis
Raw material Wt. %
POLYOLS(stage1) 26.34 (within select 18-23 % range considering 70% solid content, hence(X) 0.7 to see corroboration with Tables 6-7)
MIX-XYLENE 17.96
Methoxy propyl acetate(MPA) 4
Pre mixture
Styrene 20
Butyl acrylate 29.5
TERTIARY BUTYL PER BENZOATE 2
TERTIARY BUTYL PER BENZOATE 0.2
100

Synthesis of said hybrid polyols comprised of the steps of:
Charging the synthesized oil-modified polyester and/or alkyd polyols having polymerizable unsaturation as obtained from the previous step and mix-xylene/MPA in the reactor with stirring;
Raising the temperature of the batch to 128-132 deg C and continuing for 5-10 minutes;
Adding the premixtureas obtained by mixing the reagents/monomers styrene, butyl acrylate and catalyst tButyl perbenzoate with the amounts as mentioned in Table-4 from monomers vessel through metering pump at a controlled rate over a time period of 180 minutes sustaining temperature at 128-132°C throughout monomer addition;
Continuing further for50 minto 70 min preferably 60 more minutes at 128-132°C temperature after addition of remaining initiator.
The obtained reaction mixture after cooling affords a clear liquid with ~70% solid/ copolymer content in mix-xylene having Gardner color value below 2,hydroxyl content 1.5 to 6.5%, which is 50-80 mg KOH/gof said hybrid polyol copolymer. The same hybrid polyols upon curing with selective polyisocyanate provides coating with excellent non yellowing/good weathering performance.
Stage-III
Process for coating application of hybrid polyol
The hybrid polyol obtained fromabove, wasfurther reacted with isocyanates preferably Desmodur® N 75 BA having %NCO 16.5 to provide final coating films.
In a typical method75 gmof hybrid polyol resin (as obtained from the previous step) and 25 gram of Desmodur® N 75 BA are mixed together. For spray application the same is thinned up to 50% by using Mix-XYLENE
SOLVENT RESISTANCE RUB TEST – ASTM D4752: ASTM D4752 involves rubbing the surface of a baked film with cheesecloth soaked with O-xylene until failure or breakthrough of the film occurs. The type of cheesecloth, the stroke distance, the stroke rate, and approximate applied pressure of the rub are specified. The rubs are counted as a double rub (one rub forward and one rub backward constitutes a double rub).
Accelerated weathering simulates damaging effects of long term outdoor exposure of materials and coatings caused by sunlight and water as rain or dew. The effects are measured by exposing test samples to varying conditions of the most aggressive components of weathering - ultraviolet radiation, moisture and heat. A QUV test chamber uses fluorescent lamps to provide a radiation spectrum centered in the ultraviolet wavelengths. Moisture is provided by forced condensation, and temperature is controlled by heaters.
Also there is a limitation to involve acrylate and/orstyrene monomers in certain desired levels as demonstrated in Table 3 above and further in Tables 5, 7 below to favour further curing with isocyanates to give superior non-yellowing/good weathering performance and good mechanical and curing properties.

Table 5: % of Styrene in Oil modified Polyol (OMP)-acrylate hybrid effects in QUV (Durability):

Lower minimum Select value Overuse
%Styrene 20 23 29.5
QUV >500 Hrs 70-80% Gloss retention >500 Hrs 60-70 % Gloss retention Fails in QUV (less than 50 % Gloss retention)

Table 6:% of Oil modified Polyol (OMP) in polymer hybrid in effects in QUV (Durability):
Lower minimum Select range Overuse
% OMP(oil modified polyol) in acrylic hybrid <17 18-23 >23
QUV > 500 Hrs 70-80% Gloss retention. >500 Hrs Gloss retention Yellowing and gelled in acrylation.
The selective % of the oil modified polyol (OMP)having olefinic and/or vinylic unsaturation in the hybrid polyol ranges from 15-22% [as mentioned in the next table] and when the amount of OMP is either more or lesser than the specified limit – the desired attributes of the invented coating is not obtained.
Table 7:-Ratio of Polyol: Styrene/Acrylic
%Polyol (OMP) % Styrene % Other acrylates monomer Results
15-22 29 19-26 500 Hrs 70-80% Gloss retention
15-22 <23 28-32 >500 Hrs 70-80% Gloss retention
15-22 <20 30-34 >500 Hrs 80% Gloss retention

As mentioned hereinbefore the ratio of polymerizable monomers (styrene vs. butyl acrylate) with respect to the selective range of oil modified polyol (OMP)having olefinic and/or vinylic unsaturation influences the character of the hybrid or more specifically the films obtained after curing is described in the above Table 5flowing from examples 1A and 1A* of Table-3. Further higher gloss retention could be observed for higher levels of acrylic monomers as per Table 7 though good drying times could be still observed for still lower levels of acrylics as per Table 3 above, as per the scope of the present invention.
Finally, curable coating formulation obtained by using isocyanate and these coating films having a wide array of different curing rates, mechanical properties and non-yellowing/ good weathering properties.
In the primary embodiment, the present invention provides selective hybridpolyols having hydroxyl content 1.5 to 6.5% or 50-80 mg KOH/gwhich are reaction product/ graft copolymers of selective polyester and/or alkyd polyolsprecursorhaving olefinic and/or vinylic unsaturationand polymerizable monomers, said polyesterand/oralkyd polyolsbeing an esterification product of multifunctional fatty acid (soy fatty acid), phthalic anhydride as acid sources, Maleic anhydride as a multifunctional acid and unsaturation source and alcohol sources ofTrimethylolpropane, glycerol, and pentaerythritol (C(CH2OH)4.
Said polymerizable monomers either being acrylate monomers are devoid of any hydroxyl group and hence free of monomers of Hydroxy-Ethyl Acrylate (HEA), Hydroxy-Ethyl Methyl Acrylate (HEMA), Hydroxy-Propyl Acrylate (HPA), Hydroxy-Propyl Methacrylate (HPMA) or styrene and analogues or mixture thereof.
The resultantgraft hybrid polyol copolymers from reactiondiluted to a mixture having ~70% solid content with solventsproviding clear liquids possessingGardner color value below 2 together with non-yellowing/ good weathering performance.
Another embodiment of the present invention provides hybrid polyols wherein final coating formulation comprising said hybrid polymers of polyester and/or alkyd polyols is curable with isocyanate adapted for coating films exhibiting wide array of different curing rates, mechanical properties and non-yellowing/ good weathering properties based on the different hybrid polyols.

Thus the present advancement attains hybrid polyols comprising selectiveoil-modified polyester and/or alkyd polyol having polymerizable unsaturation modified with polymerizable acrylic and/or vinylic monomersdevoid of any hydroxyl group, grafted on the alkyd backbone, which hybrid when used as a coating composition along with selective isocyantes exhibitsexcellent non-yellowing/good weathering performance as evidenced by O-xylene rubs after 24 hrs and % Gloss Retention, QUV B Resistance ASTM G 53(500 hrs).