Journal of Applied Polymer Science, Vol.60, No.5, 731-734, 1996
Anionic-Polymerization of Cyclosiloxanes in Heterogeneous Medium
Anionic polymerization of various cyclosiloxanes [octamethylcyclotetrasiloxane (D-4), 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane (V-4), and hexamethylcyclotrisiloxane (D-3)] was performed. As catalysts, IRA-900 and PB-100 type anionites with benzyltrimethylammonium and 3-acrylamidopropylbenzyldimethylammonium groups, respectively, were used. The anionite with higher strongly basic exchange capacity (IRA-900) is more efficient in dimethylcyclosiloxane polymerization. PB-100 anionite with less strongly basic capacity is more active for polymerization of the V-4 monomer with bulky and electronegative substituent.