Method of dispersing silicone compositions in organic thermoplastic materials

摘要

A method of dispersing silicone compositions in organic thermoplastic materials is disclosed. The novel compositions produced by the method of the invention have a fine and relatively uniform dispersion or organosilicone in an organic thermoplastic. An organosilicone resin (A) and a predominantly linear silicone fluid (B) are first blended to substantial homogeneity to form an organosilicone alloy therefrom. The organosilicone alloy exhibits thermoplastic behavior and has a temperature-dependent complex viscosity eta *Si(T) associated therewith. Likewise the organic thermoplastic materials have a temperature-dependent complex viscosity, eta *OTP(T), associated therewith. The organic thermoplastic and the organosilicone alloy are thereafter mixed at a predetermined mixing temperature, Tm, and a predetermined shear strain rate. The organic thermoplastic material and the organosilicone alloy are both in a flowable state at Tm. The value of Tm is selected to be about +/-30 DEG C. of a temperature, T0, wherein the absolute value of {72*OTP(T0)- eta *Si(T0)} is at its lowest value, at the predetermined shear strain rate.