Simulation and experimental analysis of PLA/PBS/ sugarcane fiber composites prepared by vibration-triple-screw

This study focuses on a ternary system composed of PLA, PBS, and sugarcane fiber, integrating numerical simulations and experimental approaches to systematically investigate how vibration-assisted triple-screw extrusion influences flow characteristics, interfacial structure, and the overall properties of the composites. Simulation results demonstrate that the vibrational force field introduces a periodic stretching effect in addition to conventional shear, significantly enhancing the mixing index and local shear stress, which in turn improves fiber dispersion and interfacial wetting. Experimental results reveal that, under optimal amplitude and frequency conditions, fiber pull-out is markedly reduced, while elongation at break, tensile strength, and impact strength all increase significantly. Specifically, at 0.6 mm/9 Hz, tensile strength increases by approximately 15%, and impact strength rises by nearly 59%, alongside a substantial improvement in thermal stability. Additionally, Raman spectroscopy and XRD analyses confirm that vibration processing promotes molecular chain alignment and localized crystallization, while interfacial energy dissipation plays a critical role in enhancing toughness. This study clarifies the structure-performance control mechanism of vibration-assisted three-screw extrusion, providing new insights for the design and engineering applications of high-performance biodegradable fiber-reinforced composites.