Anionic and Cationic Ring-Opening Polymerization of 2,2-Divinyl-4,4,6,6-tetramethylcyclotrisiloxane. Synthesis of Regular Poly[2,2-bis(perfluoroalkyl-1‘H,1‘H,2‘H,2‘H-dimethylsilylethyl)-4,4,6,6- tetramethyltrisiloxanes] by Chemical Modification of Regular Poly(2,2-divinyl-4,4,6,6-tetramethyltrisiloxane)

Abstract

Anionic ring-opening polymerization of 2,2-divinyl-4,4,6,6-tetramethylcyclotrisiloxane yields regular poly(2,2-divinyl-4,4,6,6-tetramethyltrisiloxane), while cationic ring-opening polymerization of 2,2-divinyl-4,4,6,6-tetramethylcyclotrisiloxane yields copoly(dimethylsiloxane/divinylsiloxane). The mechanisms of both anionic and cationic ring-opening polymerizations are discussed. Chemical modification of poly(2,2-divinyl-4,4,6,6-tetramethyltrisiloxane) has been achieved by platinum-catalyzed hydrosilylation reactions with both 3,3,3-trifluoropropyldimethylsilane and perfluorooctyl-1‘H,1‘H,2‘H,2‘H-dimethylsilane. Polymers and monomer have been characterized by 1H, 13C, 19F, and 29Si NMR as appropriate. Molecular weight distributions of polymers have been determined by GPC and their thermal properties measured by DSC and TGA.