POLYANHYDRIDER OG FORMULERINGER TIL OVERTRAEK INDEHOLDENDE SAADANNE

摘要

A novel polyanhydride having at least two cyclic carboxylic acid anhydride groups per molecule also contains pendent amine groups, the proportion of amine groups to cyclic carboxylic acid anhydride groups being no more than 4:1 and the content of free carboxylic acid groups, if any are present, being less than 200 mole per cent based on the amine groups. A coating composition comprises (A) a hydroxy component having at least two free hydroxy groups per molecule and (B) an anhydride component having at least two cyclic carboxylic acid anhydride groups per molecule, at least one of (A) and (B) being a film-forming polymer. The anhydride component (B) contains a catalytically effective amount of pendent amine groups for accelerating the curing reaction between the hydroxy groups of (A) and the anhydride groups of (B) and is preferably one of the novel polyanhydrides.