A FAST CATALYST SYSTEM FOR THE RING-OPENING POLYMERIZATION OF CYCLOSILOXANES

Methanol, in combination with a non-ionic phosphazene base, was used to initiate the polymerization of octamethylcyclotetrasiloxane. In bulk, an instantaneous and large increase in viscosity was observed upon addition of the initiator. In toluene solution, the equilibrium state was reached in approximately 1 min. In addition to its high polymerization rate, another advantage of this system, as compared with e. g. alkali metal hydroxides, is that it is homogeneous.