Properties and characterization of filled poly(propylene) composites crosslinked through siloxane linkage

Abstract

The silence-grafting and water-crosslinking of poly(propylene) (PP) and its composites with calcium carbonate are described. Particular consideration is made on the properties and characterization of the grafted- and crosslinked-products. Silane-grafting of the polymers was performed in the melt by the use of vinyltrimethoxysilane and dicumyl peroxide. The results show that during the grafting process, PP chain-scission was accompanied as a side reaction. Peroxide concentration was found to be a major factor in determining the extents of grafting and PP degradation. After conducting a crosslinking reaction, the degree of crosslink determined from the direct measurement of gel content and indirect method by evaluating FTIR data was compared. The effects of silane crosslink on the thermal and mechanical properties of the PP composites were discussed. A combined effect of filler and silane crosslink network in enhancing composite modulus, tensile stress, heat distortion, and decomposition temperatures is evident. © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.