Relationship between fiber chemical treatment and properties of recycled pp/bamboo fiber composites

This article reports the preparation of recycled polypropylene (RPP)/bamboo fiber (BF) composite via direct melt blends using a twin screw extruder. The effects of the chemical treatment of BF surface (alkaline and acetylation) on fiber structure and composite mechanical, thermal, rheological properties have been investigated. We showed that alkali treatment increases the contact surface of BF within composites, resulting in a more homogenous dispersion of fibers in the polymer matrix. Alkali treatment improves mechanical properties such as tensile strength as well as the Charpy impact strength. Reinforced composites obtained with acetylated BF show better mechanical properties due to grafting of acetyl groups onto the cellulose fiber surface and thus improve compatibility between BF and matrix. The rheological properties of RPP/BF composites depending on the BF content and treatment methods are also analyzed. Predominant factors that influence the properties of relevant materials are identified. Maleic anhydride grafted polypropylene is used as a compatibilizer to improve the adhesion between the cellulosic phase and the RPP matrix.