Enhancing mechanical properties of high‐density polyethylene/polydopamine‐modified basalt fiber composites via synergistic compatibilizers

Abstract The mechanical properties of polymer‐based composites are generally determined by the interfacial adhesion between the inorganic component and the polymer itself. In this work, high‐density polyethylene (HDPE) composites were prepared with polydopamine(PDA)‐modified short basalt fibers (D‐BF) as an inorganic filler, in which the interface between HDPE and D‐BF was mediated by maleic anhydride‐grafted polyethylene (PE‐ g ‐MAH) and maleic anhydride‐grafted poly(ethylene‐ co ‐octene) elastomer (POE‐ g ‐MAH). The adding mass ratio of both the compatibilizers had a significant effect on the mechanical properties of the prepared HDPE/D‐BF composites. When total 5 wt% of both PE‐ g ‐MAH and POE‐ g ‐MAH with a mass ratio of 1/3 was introduced, the tensile strength and elongation at break of the composite containing 2.5 wt% D‐BF reached 53.7 ± 0.8 MPa and 1174 ± 17%, respectively, about 73% and 157% higher than those of the pristine HDPE. Therefore, this work demonstrated a feasible way to prepare polymeric composites with high strength and high toughness via the dual‐compatibilizer and PDA modification of the fillers.