TERTIARY ALCOHOL-DIBLOCKED DIISOCYANATE UREA URETHANE OLIGOMERS AND COATING COMPOSITIONS COMPRISING SAME

摘要

ABSTRACTThis invention provides polymer forming resinsystems and high solids solvent based chain-extendable,crosslinkable coating compositions comprising same. Theinvention comprises a polyepoxide, preferably a diepoxide,of molecular weight between about 100 and about 1000 usedgenerally in amounts from about 10% to about 50% by weightof total resin, and novel diblocked dilsocyanate ureaurethane oligomers of molecular weight between about 300and about 5000. The resin components providechain-extension polymerization during cure at elevatedtemperature, in situ, on the surface of a substrate. Theresin system is self-crosslinking. That is, no additionalcrosslinking component is required. The cured coatings ofthe invention provide greatly improved physicalproperties, in particular greatly improved corrosionresistance.