Cyclolinear organosilicon copolymers with monocyclic fragments in the sidechain

The reaction of heterofunctional condensation of organodichlorosiloxycyclot ri(tetra, penta) siloxanes and organodichlorosililcarbocyclotrisiloxane wit h dihydroxydimethylsiloxanes in the presence of pyridine was investigated. It was shown that at small lengths of the linear dimethylsiloxane link (n l ess than or equal to 4) the reaction of heterofunctional condensation runs both intermoleculary with formation of polymers and intramoleculary with fo rmation of bicyclo-organosiloxanes. It was established that insertion of cy clic fragments in the side chain hinders the chain transfer reactions that proceed with release of the D-type cycles during thermal depolymerization. The conformational and hydrodinamic properties of some polymethylsiloxane c opolymers with cyclosiloxane fragments in the side chain have been studied. (C) 1999 John Wiley & Sons, Inc.