摘要 |
This invention is a solventless process for anionically polymerizing polysiloxane polymers. No volatile hydrocarbon solvent is used. A cyclic siloxane monomer and any comonomer are introduced into a molten polymer phase of a low molecular weight polymer that has a melting point within the polymerization temperature range for the cyclic siloxanes and the comonomer, for example, 30 to 80° C. which is the melting point range for polyethylene wax which is preferred. A non-volatile hydrocarbon oil with a melting point in this range may also be used, especially if a final polymer containing oil is desired. The cyclic siloxane monomer is anionically polymerized in the molten polymer phase or the oil at 30 to 150° C. Ethylene and styrene are preferred comonomers. The low molecular polymer or non-volatile oil is not separated from the polysiloxane after termination of the polymerization.
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