Abstract: Thermoplastic compositions and composites are produced which have fewer and smaller voids with more consistent dimensions compared to conventional unreinforced and fiber reinforced thermoplastics. The high modulus thermoplastic contains silicone semi-interpenetrating polymer networks which are formed by vulcanization within the thermoplastic and initiated during melt processing. Parts molded from the compositions are more homogeneous, with evenly distributed voids, thus reducing the possibility of strss fractures. The compositions are particularly useful in the molding in thick cross-section and variable thickness parts and have been found to have increased thermal stability.

Abstract: High modulus thermoplastic compositions and composites are produced which exhibit enhanced melt integrity and strength, allowing the composites to be melt-drawn to smooth surfaced, high tolerance profiles, such as thin-walled tubing, wire, coatings, films, etc. The melt integrity is improved by adding to the thermoplastic prior to or during thermoplastic melt processing a silicone component which will be vulcanized within the thermoplastic to form a silicone semi-interpenetrating polymer network initiated during the melt processing of the thermoplastic. The composition contains about 0.1 to 20, and preferably about 1 to 4 weight percent of the silicone network, and may also contain fibrous reinforcement and/or filler/modifiers.