Bioinspired polydopamine deposition and silane grafting modification of bamboo fiber for improved interface compatibility of poly (lactic acid) composites

[Display omitted] •Polydopamine modification bamboo fibers are effective to reinforce composites.•The fibers form a hybrid network with silane-polydopamine.•High interfacial adhesion develops between the fibers and PLA.•The composite obtained excellent mechanical properties with the proposed method. The surface of bamboo fiber (BF) has poor interface compatibility with the surface of the poly (lactic acid) (PLA), which compromises composite performance. In this study, a bioinspired polydopamine (PDA) function coating was constructed on a BF surface to act as a bridge to introduce an epoxy-functionalized silane layer (KH560). The results of the test confirmed that KH560 was successfully grafted onto the surface of the BF. Therefore, the flexural, tensile, and impact strength of the modified composites increased by 37.22%, 49.64%, and 26.66%, respectively, compared with that of the untreated composites. Furthermore, the PDA-KH560-modified BF enhanced the PLA composites’ thermal stability. This strategy is assumed to provide a simple and green method for improving interface adhesion strength and potentials for future manufacturing of high-performance composites.