PP/wollastonite/bamboo flour ternary composite materials with improved thermal and mechanical properties

Based on the micro-structure of wollastonite (WS) and bamboo flour (BF), a series of PP/WS/BF ternary composite materials are prepared using blending, twin-screw melt extrusion, and injection molding processes. The experiment shows that the formulation and processing technology play a significant impact on the structure, thermal, and mechanical properties of the composites. BF has a significant impact on the nucleation and crystallization of PP, while WS has almost no effect on PP. BF improves tensile strength and enhances the strength of composites; WS improves the bending strength and flexural modulus and enhances the rigidity of composites. Taking the W-B-30-1:3 sample as an example, its tensile performance is the highest at 23.33 MPa, as well as bending strength and flexural modulus of 26.23 and 904.67 MPa, respectively. The combination of BF and WS leads to an increase in storage modulus, a decrease in loss modulus, a decrease in loss factor, an increase in glass transition temperature, and a decrease in bonding factor of ternary composite materials. This work can enrich the scope of PP composite materials, and the composite materials are expected to have potential applications in the fields of automotive interior parts with lightweight.Highlights Heterogeneous bonding among fillers enhances crystallization of composites. Wollastonite is more conducive to improving the thermal stability of composites. Adding fillers can more effectively enhance mechanical properties. The use of fillers increases interfacial compatibility and bonding performance.