The utilization of cotton stalk bark to reinforce the mechanical and thermal properties of bio-flour plastic composites

Abstract The purpose of this investigation was to evaluate the properties of bio-flour-filled composites. The composites used in this study were prepared from polypropylene, wood flour (WF) and cotton stalk bark (CSB). CSB was added with different concentrations (2.5 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 30 wt.%). Maleic anhydride grafted polypropylene (PP-g-MA) was served as a compatibilizer to increase the interfacial adhesion between the ingredients. Water absorption, morphology, mechanical and thermal properties were investigated. The results indicated that the flexural properties and tensile modulus of cotton stalk bark plastic composites (CSBPCs) were increased with the increasing concentration of CSB. However, the tensile strengths exhibited a negative correlation with the CSB content, which reached 32.9 MPa when the adding of CSB was 30 wt.%. The moisture absorption of CSBPC showed a higher value than that of neat PP, and it was increased with the increasing concentration of CSB. The thermal experiments showed that the decomposition temperatures of CSBPCs were higher than that of PP.