Influence of interfacial structure between particles and matrix polymer on mechanical properties of CaCO{sub}3 particles/polypropylene composites

摘要

The Influence of interfacial structure of Polypropylene (PP)/CaCO{sub}3 (mean particle size; 0.9 μm and 2.0 μm) modified with oleic acid and maleic anhydride-PP (MAh-PP) on mechanical properties of the composites was investigated. Scanning electron microscopy observation of the cross sections of the composites showed that the modified CaCO{sub}3 particles were dispersed homogeneously in the matrix and that CaCO{sub}3 modified with MAh - PP (MAh - PP-CaCO{sub}3) were more tenaciously adhered on PP than CaCO{sub}3 modified with oleic acid (Oleic-CaCO{sub}3). The compound of Oleic-fine particle CaCO{sub}3 (0.9 μm) improved the impact strength of PP. The maximum impact strength of the composites was 7OkJ·m{sup}(-2) at φ{sub}f of 0.08 (20wt%). The yield strength of PP/Oleic -CaCO{sub}3 decreased gradually with increase in φ{sub}f. The modification of CaCO{sub}3 by MAh-PP improved the yield strength of PP. However, the impact strength and elongation at break of the composites decreased remarkably with increase in φ{sub}f. The results suggested that the voids were formed easily at the interfaces between matrix and Oleic - CaCO{sub}3 than at the interfaces between matrix and MAh - PP- CaCO{sub}3, and that the MAh - PP was strongly connected between matrix PP and CaCO{sub}3 surfaces.