Abstract: A series of polypropylene compounds modified by calcium pimelate (CaHA) were prepared by a meltblending method, and their mechanical performance, thermal properties and fracture surface were investigated extensively. The results indicated that CaHA could well act as a βform nucleating agent to promote a crystalline transformation from αform crystals to the β one in PP. The compounds achieved optimum mechanical performance when 1.0 wt % of CaHA was incorporated into PP, and their impact strength，tensile strength and flexural strength reached 32.79 kJ/m2, 38.8 MPa and 31.6 MPa, respectively.

Key words: polypropylene, calcium pimelate, β nucleating agent, mechanical property