Process for the production of porous moldings
AssigneeHoechst Aktiengesellschaft
InventorsSabine Gorden, Hermann van Laak, Holger Schmitz
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Abstract
Porous moldings of ultrahigh-molecular-weight polyethylene obtained by injection molding polyethylenes having an intrinsic viscosity of 500 to 5000 ml/g, a mean particle size of 100 to 1500 .mu.m, and a bulk density of at least 0.35 g/cm.sup.3. The polymer is preferably molded in an injection-molding machine at 160.degree. to 260.degree. C. and an injection pressure of 80 to 150 MPa. The ratio between the flow distance of the material in the injection mold and the wall thickness of the molding is a maximum of 7.5.
Claims7
A process for the production of a porous molding having a wall thickness, said process comprising injection into a mold having a flow distance, of pulverulent, ultrahigh-molecular-weight polyethylene having an intrinsic viscosity of 500 to 5000 ml/g, a mean particle size of 100 to 1500 .mu.m, and a bulk density of at least 0.35 g/cc, said injection taking place at an injection temperature of 160.degree. to 260.degree. C. and an injection pressure of 80 to 150 MPa, a ratio of said flow distance to said wall thickness not exceeding 7.5.
Dependencies are inferred from the claim text.