Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Mixing of two or more solid polymers; mixing of solid...
Patent
1991-12-31
1994-04-19
Seidleck, James J.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Mixing of two or more solid polymers; mixing of solid...
525102, 525131, 525167, 525183, 525207, 525406, 525454, C08L 3100, C08L 3500, C08L 7102
Patent
active
053046072
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to a coating composition capable of curing at ambient temperature.
BACKGROUND ART
U.S. Pat. No. 4,452,948 describes a coating composition suitable for use as a glossy pigmented coating for a rigid substrate, particularly where hardening of the coating at ambient temperatures is required, for example as a vehicle refinishing paint. The coating composition comprises a hydroxy component having at least two free hydroxyl groups per molecule and an anhydride component having at least two cyclic carboxylic acid anhydride groups per molecule, at least one of these components being a film-forming polymer. The composition also includes a catalytically effective amount of amine groups for accelerating the curing reaction between the hydroxyl groups and the anhydride groups. The amine groups are preferably incorporated in the molecule of the hydroxy component. Tertiary amine groups are preferred although certain secondary amine groups, for example those containing tertiary alkyl groups such as polymerised units of t-butylaminoethyl methacrylate, can be used.
European Patent 73022 describes an anhydride-functional polyester and claims its use as a hardener for compounds having free epoxide, amine or hydroxyl groups. European Patent Application 282184 describes a grease-compatible, plasticiser-extended encapsulant for spliced electrical or optical cable comprising an anhydride-functionalised composition and a crosslinking agent such as a polyol, polyamine or polythiol.
European Patent Application 259172 describes a coating composition comprising an anhydride polymer containing at least two cyclic carboxylic acid anhydride groups and a polymer containing at least two functional groups reactive with anhydride groups. These reactive groups are selected from hydroxyalkylamino, hydroxyalkoxyalkylamino, hydroxy-substituted acyloxyalkylamino, hydroxy-substituted polyacyloxyalkylamino, mercaptoalkylamino and oxazolidino groups. One of the polymers comprises a flexible polymer chain selected from polyether, polyester, silicone, diene polymer, hydrogenated diene polymer, polyurethane, polyisobutylene and polyacrylate chains. The functional groups characteristic of that polymer are each present as a terminal group at the end of a flexible polymer chain. The cured coatings have increased resistance to impact and abrasion. The hydroxyalkylamino groups are preferably tertiary amino groups but can be secondary amino groups formed for example from the reaction of a primary amino group with an epoxide or from the reaction of a carboxy-tipped polymer with N-hydroxyethyl imine.
Disclosure of Invention
A coating composition according to the present invention comprises (A) an anhydride-functional polymer containing at least two cyclic carboxylic acid anhydride groups per molecule and (B) an amine-functional polymer and is characterised in that the amine-functional polymer (B) contains at least two secondary amine groups per molecule, the polymer (B) being substantially free from hydroxy and ether oxygen atoms and amino nitrogen atoms in the alpha and beta positions with respect to the amine nitrogen atoms, and the carbon atoms directly bonded to the amine nitrogen atoms not being tertiary carbon atoms.
By secondary amine groups we mean groups in which an --NH-group is directly bonded to two carbon atoms which themselves are directly bonded only to carbon or hydrogen atoms. By tertiary carbon atoms we mean carbon atoms which are directly bonded to three other carbon atoms.
The amine-functional polymer (B) is preferably substantially free from hydroxyl groups. The number of primary amine groups in polymer (B) preferably amounts to no more than 10% of the total number of primary and secondary amine groups in the said polymer.
The coating compositions of the invention cure by reaction of the anhydride groups of polymer (A) with the secondary amine groups of polymer (B) to form amide linkages. The resulting cured polymer with amide crosslinks is more resistant to hydrolysis than the polymers of U.S.
REFERENCES:
patent: 3985928 (1976-10-01), Watanabe et al.
patent: 4452948 (1984-06-01), Marrion et al.
patent: 4497663 (1985-02-01), Fisher et al.
patent: 4510274 (1985-04-01), Okazaki et al.
patent: 4798745 (1989-01-01), Martz et al.
patent: 4798746 (1989-01-01), Claar et al.
patent: 4876921 (1989-10-01), Yasui et al.
Courtaulds Coatings (Holdings) Limited
Hamilton, III Thomas
Seidleck James J.
LandOfFree
Coating compositions does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Coating compositions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coating compositions will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-20266