POLYMERS FROM MULTIFUNCTIONAL ISOCYANATES 14 - ALTERNATING COPOLYMERSFROM ISOCYANATO ALKENES - COPOLYMERIZATION OF 2-PROPENYL ISOCYANATE WITH TRIMETHYLSILYL METHACRYLATE AS ELECTRON-ACCEPTOR MONOMER

The copolymerization of 2-propenyl isocyanate (1) with trimethylsilyl methacrylate (2) has been investigated. 1 is an electron donor monomer with little tendency to undergo homopolymerization, while 2 is an ele ctron acceptor monomer, capable of free radical homopolymerization. Po lymerization to low conversion in benzene gave copolymers with prefere ntial incorporation of 2 and a tendency towards alternating copolymers with increasing amounts of 1 in the feed (1:1.13 with a 9:1 feed rati o of monomers 1 : 2). The glass transition temperatures of the amorpho us polymers are in the range from 100-70 degrees C, with a T-g of poly (trimethylsilyl methacrylate) being 135 degrees C. Desilylation occurs in the presence of water, causing an exothermal reaction above the gl ass transition temperature probably with formation of amides, a reacti on that can be used for crosslinking. (C) 1998 John Wiley & Sons, Inc.