Radical polymerization behavior of trimethoxyvinylsilane

Abstract

AbstractTrimethoxyvinylsilane (TMVS) was quantitatively polymerized at 130 °C in bulk, using dicumyl peroxide (DCPO) as initiator. The polymerization of TMVS with DCPO was kinetically studied in dioxane by Fourier transform near‐infrared spectroscopy. The overall activation energy of the bulk polymerization was estimated to be 112 kJ/mol. The initial polymerization rate (Rp) was expressed by Rp = k[DCPO]0.6[TMVS]1.0 at 120 °C, being closely similar to that of the conventional radical polymerization involving bimolecular termination. The polymerization system involved electron spin resonance (ESR) spectroscopically observable polymer radicals under the actual polymerization conditions. ESR‐determined apparent rate constants of propagation and termination were 13 L/mol s and 3.1 × 104 L/mol s at 120 °C, respectively. The molecular weight of the resulting poly(TMVS)s was low (Mn = 2.0–4.4 × 103), because of the high chain transfer constant (Cmtr = 4.2 × 10−2 at 120 °C) to the monomer. The bulk copolymerization of TMVS (M1) and vinyl acetate (M2) at 120 °C gave the following copolymerization parameters: rl = 1.4, r2 = 0.24, Q1 = 0.084, and e1 = +0.80. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5864–5871, 2005