Abstract: The invention disclosed herein is a synthetic reinforcing strand of filaments in which the strand density is reduced by spacing the filaments apart along their length with heat expandable hollow particles such as plastic microspheres expanded into microballoons and the method of making such strands. Also embodied in the invention are methods utilizing such strands in processes for making composite structures.

Abstract: The present invention is a method of producing an extruded composite comprising the general steps of: (a) extruding a longitudinally oriented composite precursor coextrusion comprising: (1) at least one thermoplastic polymeric material and (2) a core mixture of at least one thermosetting resin and at least one filler material; whereby the thermoplastic polymeric material(s) is extruded so as to substantially enclose a space, and whereby the core mixture is pumped into the space; and (b) maintaining the composite precursor under conditions whereby the at least one thermoplastic polymeric material becomes cooled and the at least one thermosetting resin becomes cured so as to form the extruded composite of the present invention.