No abstract

An alternative process to the conventional melt compounding for the incorporation of paper fibers into polyolefins was developed, based on the dispersion of paper fibers in a hot polyolefin solution and the subsequent precipitation of the polymer by cooling, which leads to an homogeneous polyolefin/paper compound. The hardness, tensile and dielectric properties of composite specimens prepared by compression molding of the obtained compound, with filler content ranging from 0 to 40% (w/w), were examined. The tensile strength of the examined composites decreases especially in the case of high-density poly(ethylene) (HDPE) and poly(propylene) (PP) composites at relatively higher filler content. The modulus of elasticity was improved only for the low-density poly(ethylene) (LDPE) composites, in comparison with unfilled specimens, and this behavior is in agreement with the observed improvement in the hardness values of these composites. Dielectric spectroscopy has been used as a characterization method of the prepared composites. It was found that the addition of newspaper fibers to the polyolefins does not significantly affect the insulating properties of the materials. In conclusion, it seemed that polyolefin/paper fiber composites with acceptable properties can be prepared by the solution/precipitation technique studied in this work.