Coating compositions including a polyisocyanate chain extended NH functional prepolymer

Patent metadata

Field	Value
Publication number	US-10519336-B2
Application number	US-201514885329-A
Country	US
Kind code	B2
Filing date	Oct 16, 2015
Priority date	Oct 16, 2015
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

This disclosure relates to a coating composition including a polyisocyanate chain extended NH functional pre-polymer, a method for coating of a metallic or plastic substrate as well as the use of the polyisocyanate chain extended NH functional pre-polymer for improving the adhesion of a coating composition on a metallic or plastic substrate and/or for improving the adhesion between two adjacent layers of multiple layers and the use of the coating composition in a one-component coating composition or two-component coating composition.

First claim

The invention claimed is:

1. A coating composition comprising a polyisocyanate chain extended NH functional pre-polymer, wherein the polyisocyanate chain extended NH functional pre-polymer
a) is free of isocyanate groups,
b) has an NH equivalent weight of from 300 to 5,000 g, and
c) consists of a reaction product that is made by reacting a reaction mixture consisting of:
(c1) at least one polyisocyanate selected from the group consisting of: 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (IPDI), 1,5-pentane diisocyanate, 4,4′-diisocyanatocyclohexylmethane, hexamethylene diisocyanate (HDI), 1,1′,6,6′-tetramethyl-hexamethylene diisocyanate, p- or m-tetramethylxylylene diisocyanate, 2,2′,5 trimethylhexane diisocyanate, aromatic polyisocyanates, toluenediisocyanate, diphenylmethanediisocyanate, and mixtures thereof, and
(c2) a NH functional pre-polymer, and
(c3) optional solvents and reaction catalysts,
wherein the NH functional pre-polymer consists of a reaction product that is made by reacting a reaction mixture consisting of:
(c2.1) a compound having at least one primary amine group that is an arylalkyl diamine selected from the group consisting of: 1,3- and 1,4-cyclohexane diamine, 5-amino-1,3,3-trimethyl-cyclohexanemethanamine (IPDA), norbornyldiamine, 2,4- and 2,6-hexahydrotoluylene diamine, 2,4′- and 4,4′-diamino-dicyclohexyl methane and 3,3′-dialkyl-4, 4′-diaminodicyclohexylmethanes, 3, 3′-dimethyl-4, 4′-diaminodicyclohexyl methane and 3,3′-diethyl-4,4′-diaminodicyclohexylmethane, 1,3- and 1,4 xylylenediamine, tetramethyl xylylenediamine, and mixtures thereof,
(c2.2) at least one dialkyl maleate selected from the group consisting of: dimethyl maleate, diethyl maleate, di-n-butyl maleate, di-iso-butyl maleate, di-tert-butyl maleate, diamyl maleate, di-n-octyl maleate, dilauryl maleate, and mixtures thereof,
(c2.3) at least one acrylate- and/or methacrylate-containing compound selected from the group consisting of: methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, isobutyl(meth)acrylate, sec.-butyl(meth)acrylate, tert.-butyl(meth)acrylate, cyclohexyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, isooctyl(meth)acrylate, isodecyl(meth)acrylate, lauryl(meth)acrylate, stearyl(meth)acrylate, isobornyl(meth)acrylate, tert-butylcyclohexyl(meth)acrylate, and
(c2.4) optional solvents and reaction catalysts, wherein a molar ratio of the at least one dialkyl maleate to the at least one acrylate- and/or methacrylate-containing compound is from 1:10 to 10:1.

2. The coating composition of claim 1 , wherein the NH functional pre-polymer has been obtained by first reacting the compound having at least one primary amine group with the at least one dialkyl maleate and then reacting the obtained mixture with the at least one acrylate- and/or methacrylate-containing compound.

3. The coating composition of claim 1 , wherein the NH functional pre-polymer has been obtained by reacting the compound having at least one primary amine group with the at least one dialkyl maleate in an equivalent ratio of dialkyl maleate to the compound having at least one primary amine group from 4:1 to 1:4.

4. The coating composition of claim 3 , wherein the polyisocyanate chain extended NH functional pre-polymer
a) has been obtained by reacting the NH functional pre-polymer with the at least one polyisocyanate in an equivalent ratio of NH and unreacted NH 2 groups in the mixture to equivalents of NCO groups from 2.0:0.2 to 2.0:1.8; and
b) has an equivalent ratio of NH groups to NH 2 groups from 100:0 to 50:50.

5. The coating composition of claim 4 , wherein the coating composition further comprises at least one curing agent having free isocyanate groups, wherein the at least one curing agent having free isocyanate groups is selected from the group consisting of: 1,5-pentane diisocyanate, hexamethylene diisocyanate (HDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (IPDI), bis(isocyanatocyclohexyl)-methane, 1,1,6,6-tetramethyl-hexamethylene diisocyanate, p- or m-tetramethylxylylene diisocyanate, 2,2′,5 trimethylhexane diisocyanate, aromatic diisocyanates and their adducts, mixtures thereof, and reaction products thereof.

6. The coating composition of claim 1 , wherein the coating composition further comprises one or more further ingredients selected from the group consisting of: curing catalysts, antioxidants, additives, pigments, extenders, UV absorbers/stabilizers (HALS derivatives), compounds with at least one alkoxy silane group and/or at least one epoxy group, hydroxyl functional binders, inorganic rheology control agents, organic sag control agents based on polyurea and/or polyamide, and mixtures thereof.

7. The coating composition of claim 5 , wherein the coating composition is one component of a two-component coating composition.

8. A method for coating of a metallic or plastic substrate, the method comprising the steps of:
a) applying a coating composition to at least a portion of a metallic or plastic substrate to be coated, wherein the coating composition comprises a polyisocyanate chain extended NH functional pre-polymer, wherein the polyisocyanate chain extended NH functional pre-polymer
1) is free of isocyanate groups,
2) has an NH equivalent weight of from 300 to 5,000 g, and
3) consists of a reaction product that is made by reacting a reaction mixture consisting of:
(c1) at least one polyisocyanate selected from the group consisting of: 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (IPDI), 1,5-pentane diisocyanate, 4,4′-diisocyanatocyclohexylmethane, hexamethylene diisocyanate (HDI), 1,1′,6,6′-tetramethyl-hexamethylene diisocyanate, p- or m-tetramethylxylylene diisocyanate, 2,2′,5 trimethylhexane diisocyanate, aromatic polyisocyanates, toluenediisocyanate, diphenylmethanediisocyanate, and mixtures thereof, and
(c2) a NH functional pre-polymer, and
(c3) optional solvents and reaction catalysts, wherein the NH functional pre-polymer consists of a reaction product that is made by reacting a reaction mixture consisting of:
(c2.1) a compound having at least one primary amine group that is an arylalkyl diamine selected from the group consisting of: 1,3- and 1,4-cyclohexane diamine, 5-amino-1,3,3-trimethyl-cyclohexanemethanamine (IPDA), norbornyldiamine, 2,4- and 2,6-hexahydrotoluylene diamine, 2,4′- and 4,4′-diamino-dicyclohexyl methane and 3,3′-dialkyl-4, 4′-diaminodicyclohexylmethanes, 3, 3′-dimethyl-4, 4′-diaminodicyclohexyl methane and 3,3′-diethyl-4,4′-diaminodicyclohexylmethane, 1,3- and 1,4 xylylenediamine, tetramethyl xylylenediamine, and mixtures thereof,
(c2.2) at least one dialkyl maleate selected from the group consisting of: dimethyl maleate, diethyl maleate, di-n-butyl maleate, di-iso-butyl maleate, di-tert-butyl maleate, diamyl maleate, di-n-octyl maleate, dilauryl maleate, and mixtures thereof,
(c2.3) at least one acrylate- and/or methacrylate-containing compound selected from the group consisting of: methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, isobutyl(meth)acrylate, sec.-butyl(meth)acrylate, tert.-butyl(meth)acrylate, cyclohexyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, isooctyl(meth)acrylate, isodecyl(meth)acrylate, lauryl(meth)acrylate, stearyl(meth)acrylate, isobornyl(meth)acrylate, tert-butylcyclohexyl(meth)acrylate, and
(c2.4) optional solvents and reaction catalysts, wherein a molar ratio of the at least one dialkyl maleate to the at least one acrylate- and/or methacrylate-containing compound is from 1:10 to 10:1, and

b) curing the coating composition applied in step a).

9. The method of claim 8 , wherein multiple layers of coating compositions are applied to at least a portion of the metallic or plastic

Assignees

• Axalta Coating Systems Ip Co

Inventors

• Huybrechts Jozef Theresia
• Enkisch-Krug Charlotte
• Tanghe Leen
• Flosbach Carmen
• Vaes Ann

Classifications

• C09D135/02 Primary

  Homopolymers or copolymers of esters (C09D135/06, C09D135/08 take precedence) · CPC title

• C09D175/02 Primary

  Polyureas · CPC title

• C08L75/02

  Polyureas · CPC title

• C08G18/3821

  Carboxylic acids; Esters thereof with monohydroxyl compounds · CPC title

• C08G18/755 Primary

  and at least one isocyanate or isothiocyanate group linked to a secondary carbon atom of the cycloaliphatic ring, e.g. isophorone diisocyanate · CPC title