Effects of the copolymer structure on the properties of polypropylene/ethylene-octene copolymer/clay nanocomposites

Morphology, rheology and mechanical properties of the nanocomposite of polypropylene (PP)/ethylene–octene random copolymer (random EOC) blend with double compatibilisers of maleated PP (PP-g-MA) and maleated EOC (EOC-g-MA) were investigated and compared with a similar nanocomposite containing a block copolymer of ethylene-octene (block EOC). The results of mechanical testing showed that both tensile and flexural modulus were similar in the two nanocomposite. However, the Charpy impact strength of the nanocomposite containing random EOC was lower. While the X-ray diffraction results showed that there was no distinct difference between the two nanocomposites, the rheological examinations indicated that the dispersion degree of clay in PP/random EOC/PP-g-MA/EOC-g-MA/clay nanocomposite was poorer. Both the formation of bigger elastomer domains and the worse dispersion state of clay in PP/random EOC/PP-g-MA/EOC-g-MA/clay are responsible for the lower impact strength of this nanocomposite.