Development of the New Polpropylene Suitable for Blow Molding

摘要

The new polypropylene (PP) suitable for blow molding has been developed. The new PP gives good controllability of parison thickness because of its very small dependence of die swell on shear rate. Furthermore, the productivity of blow molding can be improved by reducing the molding cycle time, because the cooling rate of the new PP is high. On the other hand, physical properties of the new PP has been also improved. Impact strength of the new PP is surprisingly higher than that of conventional PP and high density polyethylene for blow molding. Moreover, the new PP has advantages such as high flexibility and good transparency.