Physico-chemical study of the reaction of 1,1,5,5-tetraphenyl-3,7-dimethyl-3,7-dihydrocyclotetra-siloxane with 1,1,5,5-tetraphenyl-3,7-dimethyl-3,7-butadienecyclotetrasiloxane☆

A study was made of the reaction of hydride poly-addition of 1,1,5,5-tetraphenyl-3,7-dimethyl-3,7-dihydrocyclotetrasiloxane to 1,1,5,5-tetraphenyl-3,7-dimethyl-3,7-divinylcyclotetrasiloxane in melt in the presence of chloroplatinic acid. Independent of process conditions, poly-addition takes place in two stages and results in the formation of a crystalline polymer with a glass temperature of 338°K and a melting point of 433°K. The supermolecular structure of this polymer is characterized by spherulitic formations. Interplanar distances of the new crystalline polymer were calculated. The reaction of these monomers in solution in hexane also results in the formation of a crystalline polymer with higher crystallinity. The activation energy of the first stage of poly-addition calculated from the displacement of peaks of heat liberation under conditions of non-isothermal heating at different rates is 104·9 × 103 J/mole.