Silane-Treated Basalt Fiber-Reinforced Poly(butylene succinate) Biocomposites: Interfacial Crystallization and Tensile Properties

In this work, an economical modifier silane agent-KH550-was used for surface treatment of basalt fiber. Then, a biodegradable poly(butylene succinate) (PBS)/modified basalt fiber (MBF) biocomposite was successfully developed. The effects of silane treatment and fiber mass content on crystalline structure, isothermal crystallization process and mechanical performance of composites were evaluated. The interfacial crystallization of PBS on the surface of MBF was investigated by using a polarized optical microscope (POM). The transcrystalline (TC) structure could be clearly observed and it grew perpendicular to the surface of MBF, which boosted the nucleation ability on PBS crystallization and the strong interfacial interaction between PBS and silane-treated basalt fiber. Under isothermal crystallization kinetics, the incorporation of basalt fiber enhanced the crystallization rate and reduced the crystallization half-time values of composites compared with that of neat PBS due to a heterogeneous nucleation effect. Furthermore, tensile results confirmed that the presence of MBF could greatly improve the tensile strength and modulus. The predicted interfacial shear strength (IFSS) suggested that an enhancement of interfacial bonding could be realized via interfacial crystallization, which was also verified by SEM images. The PBS/MBF biocomposites can be applied in many fields as a low-cost, lightweight, and biodegradable composite material.