Patent ID: 8652377
Filing Date: 2014-02-18
Classification: B29C

Abstract:
1. A process for manufacturing a tubular shaped co-extruded article comprising: processing first and second polymers in an extruder apparatus to form a tubular-shaped extrudate having at least one bend, the extruder apparatus comprising: wherein said extruder barrels discharge through said extrusion die which is controllably connected to a robotic handling unit wherein said extrusion die is a moving mandrel expanding die including an inner die member and an outer die member, where the process includes off-setting the inner die member and the outer die member relative to movement of the robotic handling unit to thereby obtain tubular-shaped extrudates having constant wall thickness on the inside and on the outside of the extrudate; and solidifying the extrudate, wherein the first polymer is a thermoplastic vulcanizate comprising: a fully cured EPDM-type rubber and a polypropylene thermoplastic polyolefin, where the EPDM-type rubber is cured to an extent where less than 5 wt. % of the rubber can be extracted; and wherein the second polymer is a polyamide, and wherein the thermoplastic vulcanizate forms the outer layer (B) and the polyamide forms the inner layer (A).