| 摘要 |
PURPOSE:To produce an elastomer excellent in heat resistance, ozone resistance, and electrical insulation in high yields, by copolymerizing a cyclic phosphazene with a cyclic siloxane oligomer by using chlorosulfonic acid as a polymerization catalyst. CONSTITUTION:A cyclic phosphazene (e.g., hexachlorocyclotriphosphazene) is copolymerized with a cyclic siloxane oligomer (e.g., octamethylcyclotetrasiloxane or tetramethyltetraphenylcyclotetrasiloxane) in an organic solvent (e.g., 1,2,4- trichlorobenzene) in the presence of chlorosulfonic acid as a catalyst. Low-MW products as removed by washing with n-heptane or the like to obtain a heat- resistant elastomer comprising cyclic phosphazene oligomer units and cyclic siloxane oligomer units. |
