We are now engaged in the study of a resin flow control method of molding to positively orient molecules or fillers by displacing resin flows in the mold. This method has proved effective for improving the physical properties of glass fiber reinforced polypropylene molding. This study is aimed at improving the sealing performance of polypropylene containers by circumferentially controlling resin flows in the mold to reduce free volumes. In this paper, we evaluate the sealing performance of such molding in relation to different rotational speeds of the rotational core in the mold.

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