Evaluation of Properties of Polypropylene Matrix Composites Reinforced With Perlite, Expanded Perlite, Silanized Expanded Perlite, and Talc Fillers

Abstract

Improving the mechanical and thermal performance of polypropylene (PP) composites is essential to meet the demanding requirements of contemporary automotive, construction, and electrical-engineering applications. To address this, PP matrix composites were developed using natural and environmentally friendly fillers such as speech, perlite, expanded perlite, and silanized expanded perlite, and their physical, mechanical, morphological, and thermal properties were investigated. Composites were prepared using a twin-screw extruder with 5%, 10%, and 20% (w/w) fillers, and additives were used as PP reference samples. The samples were evaluated through density measurements, FTIR spectroscopy, color analysis, melt flow index, tensile and flexural strength testing, impact resistance, scanning electron microscopy, thermogravimetric analysis, and heat deflection temperature (HDT) testing. The results showed significant changes in the properties of the filler material used and structural composites. Thermal properties of hybrid composites showed improvement compared to neat PP for all types and ratios. The HDT values of the composites are similar to each other and to that of pure PP. The flexural strength and tensile strength values of neat PP are 22.1 and 16.2 MPa, while the flexural and tensile values for all ratios of four different inorganic additives resulted in higher values. The flexural strength of PP-P20 (20% perlite additive) composite is increased by 43%, and the tensile strength increased by 29% compared to pure PP. As expected, the values of the composites were higher compared to pure PP. The melt flow index values decreased for the additives, except for the perlite additive. The index of the additive ratios used belongs to the higher values compared to PP. The innovations obtained show that these additive ratios are effective in the development of PP matrix composites in high-performance range applications as low selection and environmentally friendly options.