Oriented thermoplastic and particulate matter composite material

A process for the continuous production of a high modulus article comprising a composite of an oriented plastic material and from about 20 to about 80% by weight of an oriented particulate material, said process including the steps of:

• (a) continuously forcing an orientable plastics material, while it is close to or at its softening temperature and in admixture with an orientable particulate material through a converging passage of which the cross-sectional area diminishes in the forward direction of plastic flow;
• (b) lubricating said admixture adjacent said passage to obtain substantially extensional flow of said admixture through said passage thereby to produce an extrudate wherein said orientable particulate material is oriented parallel in said extensional flow of said mixture;
• (c) deforming the extrudate, while it is maintained at or close to its melt temperature, to produce an oriented, deformed extrudate;
• and
• (d) cooling the deformed extrudate to preserve the orientation and provide a composite of high stiffness and high strength in flexure.