WATER-BORNE DISPERSIONS OF OIL MODIFIED URETHANE POLYMERS

摘要

A composition comprising a self-crosslinkable aqueous dispersion of a polyurethane polymer having pendant auto-oxidizable functional groups is disclosed, said composition obtainable by reacting:
(a) an organic polyisocyanate;(b) an isocyanate reactive compound containing pendant fatty acid unsaturation;(c) an isocyanate reactive polymeric polyol containing neutralizable pendant carboxylic acid groups; and(d) a reactive diluent containing at least two polymerizable, ethylenically unsaturated double bonds. The obtained polyurethane dispersion is suitable for application in self-curing coating compositions.

主权项

1. A crosslinked polyurethane film comprising an air oxidation reaction product of a film dried from a water dispersible, self-crosslinkable isocyanate terminated polyurethane prepolymer composition reacted from a mixture comprising:
a) an organic polyisocyanate component; b) an isocyanate reactive oil modified polyol component having olefinic unsaturation; c) an isocyanate reactive polymeric polyol component containing pendant anionic functional groups; and d) a reactive diluent component containing at least two ethylenically unsaturated double bonds wherein said a, b, and c are reacted to form said prepolymer, said reactive diluent is incorporated into said prepolymer, said prepolymer is optionally chain extended, said prepolymer is dispersed in a medium to form a dispersion, said prepolymer forms a film as the medium evaporates, and after film formation free radicals are generated by decomposition of peroxides formed for air oxidation of said olefinic unsaturation of said oil modified polyol component and a curing reaction occurs between said free radicals and said reactive diluent curing said film.