Properties of Recycled Natural Fiber Reinforced Composites Materials

The paper presents the results of the examinations concerning the properties of recycled polymer composites made of polylactide (PLA) and filled with various fractions from processing of fiber hemp. Filler in the form of hemp hurds and hemp straw was obtained from collaboration with Olimax NT Sp. z o.o. (Poland). Hemp hurds, hemp pulp, and hemp straw was dosed in the amount of 10% mass share of the mixture. Both polymer material and fillers were dried before the process and then the standardized samples were prepared using the injection molding technology. Tensile stress tests, hardness tests, and thermal properties tests were performed in order to determine the properties of molded pieces. After completion of primary tests, the samples were fragmented by means of the industrial low-speed mill. The obtained milling products were processed again using the injection technology, with process parameters the same as during primary processing. The obtained normalized samples were subjected again to the analysis of mechanical and thermal properties. Furthermore, the microscopic observations were performed in order to verify dispersion of the fillers in the polymer matrix.