Synthesis and characterization of polysiloxanes with pendant bicyclic fragments

Abstract

AbstractThe hydrosilylation reactions of 5‐vinyl‐2‐norbornene with α,ω‐bis(trimethylsiloxy)methylhydrosiloxane catalyzed by platinum hydrochloric acid (0.1Msolution in tetrahydrofuran), Karstedt's catalyst (Pt2[(VinSiMe2)2O]3) and platinum on the carbon have been studied. Dependence of reaction rate and active SiH bonds' conversion depth on the catalyst was investigated. Even in the excess of the 5‐vinyl‐2‐norbornene, not all active SiH groups participate in the hydrosilylation reaction. The reaction order, activation energies, and rate constants have been determined for hydrosilylation reactions in the presence of H2PtCl6. The synthesized oligomers were characterized by Fourier transform infrared spectroscopy (FTIR),1H,13C,1H‐1H correlation spectroscopy (COSY), and C,H‐correlation NMR spectroscopy. Synthesized polysiloxanes were characterized by wide‐angle X‐ray, gel‐permeation chromatography, and DSC analyses. Calculations using the quantum‐chemical semi‐empirical AM1 method for modeling reaction between methyldimethoxysilane [Me(MeO)2SiH] and 5‐vinyl‐2‐norbornene were performed to evaluate possible reaction paths. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011