Essential Work of Fracture Evaluation of Compression-Molded Polypropylene/Ethylene and 1-Octene Copolymer Blends

The influence of ethylene and 1-octene copolymer content on the fracture behavior of compression-molded polypropylene/copolymer of ethylene and 1-octene blends was evaluated by means of the essential work of fracture method. The results indicated that the approach worked well for the polypropylene/copolymer of ethylene and 1-octene blends when copolymer of ethylene and 1-octene content was 0∼7.5 wt%. The specific essential work of fracture (we) of the blends increased with increasing copolymer of ethylene and 1-octene content and the dominant factor which affected we was the necking and subsequent fracture term (we,n). The specific non-essential work of fracture (βwp) slightly increased with increasing copolymer of ethylene and 1-octene content, while the term wp showed a decreasing trend with increasing shape factor (β). The trend of w e values obtained from crack-opening displacement was similar to that of essential work of fracture tests.