Beta-crystalline form of isotactic polypropylene and method for forming the same

摘要

This invention relates to obtaining beta crystalline Phase isotactic polypropylene with high purity and thermal stability simply by melt- crystallization in the presence of a two component beta nucleating agent. The two component beta-nucleating agent is formed by mixing 0.0001- 1 weight % of dibasic acid with 0.001-1 weight % oxide, hydroxide or acid salt of a Group IIA metal. Such beta phase polypropylene can be used for the production of high impact strength molding extrusion shapes, microporous film and microporous hollow fiber.