PROCESS FOR THE PRODUCTION OF POLYMER MATERIALS

摘要

1480479 Working polymers NATIONAL RESEARCH DEVELOPMENT CORP 21 June 1974 [28 June 1973] 30823/73 Heading C3P Prior to solid phase deformation of a semicrystalline polymer having a natural draw ratio of greater than 6, the polymer is cooled from the melt at a rate of 0À1-10‹ C. per minute to obtain a material with substantially uniform morphology in cross-section. The polymer is preferably high density polyethylene or polyoxymethylene and after the cooling treatment is extruded, preferably applying a tensile haul off force to the product, at a temperature within 50‹ C. of the melting point. The elongate products having a smallest dimension above 0À25 mm. have a Young's modulus above 3 Î 1010 N/m.2 for polymethylene and above 1 Î 1010 N/ m.2 for polyoxymethylene.