REACTIVE POLYMERS INCORPORATING SILYL ENOL ETHER GROUPS .1. SYNTHESISBY RADICAL POLYMERIZATION OF 2-(TRIMETHYLSILOXY)-BUTADIENE AND 2-(TERT-BUTYLDIMETHYLSILOXY)BUTADIENE

2-(Trimethylsiloxy)butadiene (TMSBD) and 2-(tert-butyldimethylsiloxy)b utadiene (TBMSBD) were copolymerized with styrene (St) and methyl meth acrylate (MMA) under free-radical conditions. The obtained polymers we re found to contain reactive silyl enol ether groups in a ratio identi cal to the TMSBD or TBMSBD molar fraction in the copolymer. All invest igated samples displayed only 1,4- and 3,4-microstructures. The influe nce of several experimental factors on the yields, rates of polymeriza tion, microstructures, and copolymer compositions were examined. Monom er reactivity ratios r(1) and r(2) at 60 degrees C were determined fro m copolymer composition curves at low conversions. The homopolymerizat ion of TBMSBD was also investigated and results were compared with tho se previously obtained for TMSBD. A slight increase in rates was obser ved and was rationalized on the basis of the higher viscosity resultin g from the structural change in the monomer. Thermal stabilities of th e synthesized polymers were investigated by TGA and their glass transi tion temperatures were determined by DSC. All measurements are compati ble with a possible use of TMSBD and TBMSBD copolymers as reactive pol ymers. (C) 1996 John Wiley & Sons, Inc.