This paper reviewed the achievements in catalyst preparation

polymerization technology design

structure-property correlation and practical application of PP in-reactor alloys.The basic PP in-reactor alloys ranging from high rigidity to high toughness were successfully produced in the pilot experimental device for PP

which was catalyzed by the modified Ziegler-Natta catalyst with the addition of novel sulfonyl electron donor or Ziegler-Natta/metallocene complex catalyst.A series of automobile-used PP special materials

obtained by blending the basic resins with additives or natural fibers

were used to prepare typical automobile components.The molding technology and practical application of the automobile components were systematically investigated.