Macromolecules, Vol.35, No.6, 2207-2211, 2002
Poly(silyl ether)s by ruthenium-catalyzed hydrosilylation polymerization of aliphatic omega-dimethylsilyloxy ketones and copolymerization of aliphatic alpha,omega-diketones with alpha,omega-dihydridooligodimethylsiloxanes
The hydrosilylation polymerization of aliphatic omega-dimethylsilyloxy ketones is catalyzed by activated dihydridocarbonyltris(triphenylphosphine)ruthenium (Ru) to yield unsymmetrical poly(silyl ether)s. Likewise, Ru catalyzes the copolymerization of aliphatic alpha,omega-diketones with alpha,omega-dihydridooligodimethylsiloxanes to yield symmetrical poly(silyl ether)s. These polymers have been characterized by H-1, C-13, and Si-29 NMR as well as IR spectroscopy. Their molecular weight distributions (M-w/M-n) have been determined by GPC. End group analysis by H-1 NMR provides an independent measure of M-n. Their thermal stability was measured by TGA, and their glass transition temperatures (T-g's) were determined by DSC. Chiral centers affect the NMR spectra of these poly(silyl ether)s. The effect of siloxane chain length on copolymer T-g has been evaluated.