METHOD OF BLENDING HIGH-VISCOSITY SILICON

摘要

Blends of thermoplastic polymers (I) and silicone fluids (II) are produced continuously by melting one or more (I) in an extruder; injecting a high viscosity (at least 90,000 centipoise at ambient temp.) silicone fluid; and blending the mixt. during its passage through the extruder. The temp. of blending is controlled to achieve the desired dispersion, pref. by controlling the temp. of the polymer melt prior to blending. Injection pref. occurs at a point 1/3 to 1/2 the extruder length downstream from the polymer feed point. Polymer blends having desirable engineering properties and improved lame retardancy (compared with materials produced by prior art processes) are obtd. by a simple and economical process providing a high degree of dispersion with minimal degradation.