CONTROLLED POLYMERIZATION OF HEXA-N-ALKYLCYCLOTRISILOXANES WITH LONG ALKYL-GROUPS

Hexa-n-alkylcyclotrisiloxanes with side chains ranging from butyl up t o decyl were polymerized anionically with cryptated lithium as the cou nterion. The polymerizations usually yielded polymers with low polydis persity, demonstrating the presence of a single growing species and th e successful breaking up of aggregates. Formation of bimodal molecular weight distributions in the polymerization of the cyclic trimers cont aining heptyl up to decyl side chains can be explained by the presence of traces of siloxanediol, leading to some chains growing at both end s.