Paper Title
Modified Cereal Straw as Multifunctional Filler for Natural Rubber Biocomposites

Abstract
This research study aims to provide an examinations on biocomposites based on natural rubber (NR), natural straw fibers and their modifications as well as production techniques and properties. Cereal straw was alkalized and treated with different modifiers such as: benzoyl or dicumyl peroxide and acetic or maleic anhydrides. Morphological changes and thermal stability of fillers were investigated by scanning electron microscope (SEM), fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) technique. Moreover full characterization of the produced composites was also executed, which included: rheometric properties, static and dynamic mechanical properties, crosslinking density, damping properties, tear strength and resistance to simulated aging processes. Cereal straw represents interesting alternative for commercial fillers and could be successfully applied as a low-cost filler, which improved several properties of elastomer composites. Modified straws showed better thermal resistance compared to raw fibers and were resistant up to about 220°C. Increased adhesion between modified straw fibers and the elastomeric matrix was observed for 10 phr filled composites, which was confirmed by dynamic mechanical thermal analysis (DMTA). In addition, the impact of the applied modifications was confirmed by higher values of the Payne effect, which resulted from the presence of developed secondary structure of the filler in vulcanizates. Moreover, the crosslinking density of composites increased, which was reflected in the improvement of tensile properties, determined by tensile and tear strength and relative damping. Furthermore, all of the vulcanizates proved to be resistant to thermo-oxidative degradation. Keywords - Biocomposites, Cereal Straw, Modifications, Natural Rubber, Multifunctional Properties