Thermal properties—such as thermal conductivity, thermal diffusivity, and specific heat—of metal (copper, zinc, iron, and bronze) powder-filled high-density polyethylene composites are investigated experimentally in the range of filler content 0-24% by volume. Experimental results show a region of low particle content, 0-16% by volume, where the particles are distributed homogeneously in the polymer matrix and do not interact with each other. In this region most of the thermal conductivity models for two-phase systems are applicable. At higher particle content, the filler tends to form agglomerates and conductive chains resulting in a rapid increase in thermal conductivity.

This study examines the possibility of replacing partially or totally the di(2-ethylhexyl) phthalate (DEHP - low molecular plasticizer) from the poly(vinyl chloride) (PVC) compositions intended for medical devices, with poly("-caprolactone) (PCL - biodegradable, biocompatible, and macromolecular plasticizer). Nine different plasticized PVC (PVC-P) compositions are analyzed from the viewpoint of thermal and mechanical properties, plasticizer loss, and extraction behavior in different medical media. After comparing the experimental results with the data from the literature, corresponding to traditional PVC-P, it can be concluded that the PCL and even PCL-DEHP mixture behave as better plasticizers for PVC, providing a lower extraction risk and similar or even improved thermal and mechanical properties.