Abstract: The purpose of the work is to prepare and characterize hybrid fillers of cereal straw – perlite as well as to examine their impact on the functional properties of elastomeric biocomposites. Natural rubber was used as the polymer matrix, vulcanized with a sulfuric crosslinking system. The subject matter of the work included an interdisciplinary knowledge segment in the field of polymertechnology – hybrid biomaterials. The work investigated the effect of physical (mechanical) modification of lignocellulosic filler. The process of milling and homogenization of cereal straw with the addition of perlite was carried out in a planetary ball mill. The properties of biocomposites were examined in terms of two key aspects: The amount of hybrid filler and its ratio (cereal straw to natural mineral). The plate-like structure of natural minerals and the fibrous structure of cereal straw created a two-component filler, which influenced the properties of the produced biomaterials. A significant improvement in barrier, crosslinking density, hardness, mechanical and damping properties has been noted for systems containing hybrid fillers. Moreover, all vulcanizates proved to be resistant to the rmooxidative aging. Furthermore, the straw modificated with perlite formed a more complex structure in the composites, resulting in a stronger reinforcing effect, which was confirmed by dynamic-mechanical analysis (Payne effect).

Key words: hybrid fillers, straw, perlite, biocomposites, natural rubber