Polypropylene performance test methods

Tests on the fragrance/flavor barrier properties of slloxane coated polyethylene and polypropylene film, using the ASTM test method D-1653 are given In Table II, which show excellent performance for the primed film. ... 

Polystyrene itself is not used for endoprosthetic purposes and its application is accounted for only because of easy substitutions in benzene rings. The method was subsequently modified for heparinization of silicone and natural rubber, polyethylene, polypropylene, polyethylene terephthalate), and other polymers. Styrene was first grafted onto the polymers by y-radiation and then the above-described reaction was performed in the second step. All the polymers synthesized in this way contained sufficiently large amounts of immobilized heparin (2.8—15.7 ng/cm2) and displayed good thromboresistance when tested in vitro — recalcified blood was not clotted for several hours. 

First the two cavity mold configuration was tested. Four different materials were evaluated and each molded at three different flow rates. The materials were Polycarbontate, ABS, PBT and Polypropylene. All materials were prepared and processed according to the manufacturers recommended conditions. Short shot samples were collected for each of the twelve runs performed on the two cavity mold. The short shot method is based on the 5 Step Process (4) where cavities are filled to about 70% fidl. No pack or hold is used as these are all short shot samples. Short shot samples are used as they provide clearly measurable differences in cavity filling. 

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