Base catalyzed proton transfer polymerization of 1-hydroxypentamethylcyclotrisiloxane. Comparison of hyperbranched polymer microstructure and properties to those of highly regular linear analogs

摘要

Treatment of 1-hydroxypentamethylcyclotriloxane (1), an A(2)B monomer, with a phosphazene P-4-t-Bu superbase followed by quenching with phenyldimwthylchlorosilane/triethylamine leads to a hyper-branched polysiloxane (2). The microstructure and properties of 2 are compared to those of highly regular linear analogs obtained by anionic or cationic regiospecific ring opening polymerization of 1-(phenyldimethylsiloxy)pentamethylcyclotrisiloxane (3). References: 44