Abstract: A process for the continuous melt thermoforming of thermoplastic polymers is disclosed. The process comprises extruding a flat web of molten polymer in a downward direction and directly over a series of mould cavities moving at a predetermined speed thereby sequentially covering the mould cavities. A vacuum is applied to the mould cavities and the web of molten polymer is brought into contact with the surface of the mould cavity, the mould defining the mould cavity being comprised of porous metal. The polymer is cooled and the resultant article is removed from the mould. The process is controlled so that the articles thermoformed in the process are of substantially uniform thickness. In embodiments the mould cavities are located on the periphery of a continuous belt or preferably a wheel. The process may be operated with polymers of low zero shear viscosity. The preferred polymers are polyamides, especially polyhexamethylene adipamide, of relative viscosity in the range 25 to 65.

Abstract: High density polyethylene film of improved clarity and stiffness is disclosed. The improved high density polyethylene film may be manufactured from a blend of polymers comprising an ethylene polymer of density in the range about 0.950-0.965 and of melt index less than about 10, and not more than about 30% of an ethylene polymer of melt inex in the range of about 0.1 to about 10 and of density in the range about 0.910-0.945.