Weatherable and durable coating compositions

Patent metadata

Field	Value
Publication number	US-2022411661-A1
Application number	US-202017778027-A
Country	US
Kind code	A1
Filing date	Nov 12, 2020
Priority date	Dec 5, 2019
Publication date	Dec 29, 2022
Grant date	—

Abstract

A curable coating composition is provided having multi-functionalized acrylic copolymer and amino-functional silicone resin curing agents. The acrylic copolymer of the curable coating composition has, in polymerized form, epoxy functionalized groups and cure compatibility groups and the amino-functional silicone resin is an aryloxy-containing amino-functional siloxane, which optionally is derived from sterically hindered alcohol-amine precursor moieties. The coating compositions are useful in the field of superior weatherable and durable coatings and are useful to replace isocyanate-containing polyurethane based coatings. Also provided are coated articles produced from the curable composition.

First claim

1 . A curable coating composition comprising:
(1) an amino-functional silicone resin comprising in polymerized form, structural units of:
(i) (R 3 SiO 1/2 ) a ;
(ii) (R 2 Si(OR′) x O (2-x)/2 ) b ;
(iii) (RSi(OR′) y ,O (3-y)/2 ) c ; and
(iv) (Si(OR′) z O (4-z)/2 ) d
wherein each R′ is independently hydrogen, an alkyl group, a functionalized alkyl group, an aryl group or a functionalized aryl group, provided that at least 10 mole percent of all R′ groups are aryl groups or functionalized aryl groups;
wherein each R is independently hydrogen, an alkyl group, or a functionalized alkyl group;
wherein at least 10 mole percent of the combination of R and R′ groups are amine containing groups of the formula: —R a —NHR b where R a is an alkyl group or an aryl-containing group derived from an amino alcohol and R b is hydrogen or an alkyl group;
wherein a+b+c+d=1.00 (100 mole percent); x is either 0 or 1; y is either 0, 1 or 2; and z is either 0, 1, 2, or 3; and
the —NH— equivalent mass of the amino-functional silicone resin is from 50 to 750; and
(2) an acrylic copolymer which has, in polymerized form, epoxy functionalized groups and cure compatibility groups; and wherein the coating composition has a molar ratio of amine NH functionality to epoxy functionality in the range of from 0.5 to 1.3.

2 . The coating composition of claim 1 having a molar ratio of amine NH functionality to epoxy functionality in the range of from 0.8 to 1.

3 . The coating composition of claim 1 wherein at least 20 mole percent of the combination of R and R′ groups of the amino-functional silicone resin are amine containing groups of the formula: —R a —NHR b .

4 . The coating composition of claim 1 wherein from 5 to 42 mole percent of the combination of R and R′ groups of the amino-functional silicone resin are amine containing groups of the formula: —R a —NHR b .

5 . The coating composition of claim 1 wherein the amino alcohol is selected from the group which (a) has steric hindrance around the COH moiety; (b) is a secondary or tertiary alcohol; or (c) mixtures thereof.

6 . The coating composition of claim 1 wherein the amino alcohol is 1-amino-2-propanol or 1-amino-2-methylpropan-2-ol.

7 . The coating composition of claim 1 wherein from 20 to 50 mole percent of all R′ groups are aryl groups or functionalized aryl groups.

8 . The coating composition of claim 1 wherein the epoxy functionalized groups of the acrylic copolymer are derived from one or more monomers selected from the group of glycidyl maethacrylate (GMA), glycidyl acrylate, and mixtures thereof; and wherein the acrylic copolymer has an epoxy equivalent weight (EEW) in the range of 200-600.

9 . The coating composition of claim 8 wherein the acrylic copolymer comprises in polymerized form, 30-60% glycidyl (meth)acrylate monomer units by weight based on the weight of the total monomer units of the acrylic copolymer.

10 . The coating composition of claim 1 wherein the acrylic copolymer comprises in polymerized form, from 2% to 20% cure compatibility group monomer units by weight based on the weight of the total monomer units of the acrylic copolymer.

11 . The coating composition of claim 1 wherein the cure compatibility groups of the acrylic copolymer comprise monomer groups, in polymerized form, that contain one or more of alcohol (OH) functionality, a phenolic group, a tertiary amine or an acid group that is either pendant to the backbone or attached as an end group.

12 . The coating composition of claim 1 wherein the cure compatibility group is derived from hydroxyethyl methacrylate (HEMA).

13 . A coated article comprising one or more layers of a cured coating composition of claim 1 .

Assignees

• Dow Global Technologies Llc
• Dow Silicones Corp

Inventors

• Swier Steven
• Wieber Gary M
• Vogel Erin B
• Horstman John B
• Machelski Susan M

Classifications

• C08G77/38

  Polysiloxanes modified by chemical after-treatment · CPC title

• C09D183/10

  Block or graft copolymers containing polysiloxane sequences (obtained by polymerising a compound having a carbon-to-carbon double bond on to a polysiloxane C09D151/08, C09D153/00) · CPC title

• C08G77/26 Primary

  nitrogen-containing groups · CPC title

• C08L83/08

  containing silicon bound to organic groups containing atoms other than carbon, hydrogen and oxygen · CPC title

• C09D163/10

  Epoxy resins modified by unsaturated compounds · CPC title