Patent ID: 6391239
Filing Date: 2002-05-21
Classification: B29B,B29C,B29K,Y10T

Abstract:
A method of making an elongate multiphase polymeric extrudate having one phase formed of at least one additive and another phase formed of a host polymeric melt flow, said method comprising the steps of:(a) supplying a melt flow of a polymeric host material to a die assembly comprising a thin-plate assembly upstream of an extrusion die; and (b) injecting at least one additive into at least one predetermined location in a cross-section of the melt flow of the polymeric host material while passing the melt flow of the polymeric host material through the die assembly and on to the extrusion die, and (c) extruding the melt flow of the polymer host material containing the at least one additive through the extrusion die to form a multiphase extrudate thereof, wherein (d) the at least one additive is injected into the at least one predetermined location in the cross-section of the melt flow of the polymeric host material without homogeneously mixing the at least one additive and the polymeric host material such that the multiphase extrudate includes (i) one phase which is formed of the at least one additive at the at least one predetermined cross-sectional location along the lengthwise extrusion direction of the extrudate, and (ii) another phase along the lengthwise extrusion direction of the extrudate which is formed of the polymeric host material.