High-density Polyethylene - Expanded Perlite Composites: Structural Oriented Analysis of Mechanical and Thermomechanical Properties

As part of this work, research was carried out on the effect of the addition of expanded perlite (PR) on the mechanical and thermomechanical properties of high-density polyethylene (PE) composites. Composites containing from 1 to 10 wt% of the inorganic filler were produced. Polyethylene-based composites manufactured by twin-screw extrusion and formed in the compression molding process were subjected to mechanical, thermomechanical, and structural analyses. The structure of polymer composites and filler was analyzed using scanning electron microscopy (SEM). It has been correlated with the static tensile tests and results of dynamic thermomechanical analysis (DMA). As part of the work, several thermomechanical parameters were calculated, and the obtained results were discussed with the evaluation of interfacial adhesion based on microscopic analysis. The research showed that despite introducing a 10 wt% of particle-shaped filler, the composites show increased stiffness without noticeable deterioration in tensile strength, simultaneously reducing toughness and brittleness. The analysis of the thermomechanical properties showed the lack of significant effects of the filler influence on the polymer matrix.