Thermolatent catalyst and its use in curable compositions

Abstract

Tin-containing catalysts are provided comprising a compound of formula I. I: L1, L2, L3, and L4 are each independently selected from —O—, —S—, —OC(═O)—, —OC(═S)—, —SC(═O)—, —SC(═S)—, —OS(═O)O—, —OS(═O)— —N(R6)-, and —OP(═O)(R6)-, wherein R6 represents hydrogen or a monovalent aliphatic, araliphatic, cycloaliphatic or aromatic group having up to 20 carbon atoms. R1, R2, R3, R1', R2′, and R3′ each independently represent a divalent aliphatic, araliphatic, cycloaliphatic or aromatic group having up to 20 carbon atoms; and R4, R5, R4′, and R5′ each independently represent hydrogen or a monovalent residue derived from reaction of a respective N—H group with an isocyanate, an ethylenically unsaturated compound, a lactone, a dilactone, a thiolactone, a lactam, a thiolactam, a carboxylic acid or derivative thereof, or an epoxide. Also provided are curable compositions containing these catalysts and methods of controlling the rate of cure of curable compositions.