CATALYTIC HYDROSILYLATION OF DIENE-BASED POLYMERS .1. HYDROSILYLATION OF POLYBUTADIENE

The chemical modification of unsaturated polymers via catalytic hydrosilylation offers an efficient synthetic route to novel polymers containing silane functional groups. A study involving the hydrosilylation of polybutadiene polymers has been carried out in the presence of RhCl(PPh3)3. UnDer mild reaction conditions, RhCl(PPh3)3 is highly selective toward catalyzing the hydrosilylation of the vinyl C=C bonds of the polymers. The degree of hydrosilylation can be controlled by appropriate adjustment of the [silane]: [C=C] ratio. In the case of alkyl- and alkoxysilanes, the reaction mechanism involves an anti- Markovnikov addition leading to a linear adduct The microstructure of the product polymers was characterized by IR,1H NMR,13C NMR, and29Si NMR. In addition, vapor phase osmometry and gel permeation chromatography were used to determine the chain-length properties of the product polymers. © 1990, American Chemical Society. All rights reserved.