NOVEL BLOCKED POLYISOCYANATE AND USES THEREOF

摘要

Disclosed is a novel blocked polyisocyanate obtained by blocking the terminal isocyanate groups of a non-blocked polyisocyanate with a thermally dissociative blocking agent, wherein the non-blocked polyisocyanate is obtained by reacting at least one diisocyanate selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate with a polyhydroxy compound having an average number of hydroxyl groups as many as 4.5 to 10, and removing substantially all unreacted diisocyanate monomers. A coating composition comprising the blocked polyisocyanate of the present invention as a curing agent and a polyol as a main agent not only has excellent curability even under low temperature conditions, but is also capable of forming a coating which has excellent impact resistance. The blocked polyisocyanate of the present invention has excellent miscibility with a plasticizer for the blocked polyisocyanate, so that, an adhesive property-imparting composition comprising the blocked polyisocyanate and a plasticizer and/or a solvent can be combined with a plastisol to prepare a plastisol composition having excellent adhesive properties even under low temperature conditions.