Pure and Applied Chemistry

Abstract: In this research, switchgrass (SG) fiber-reinforced poly(trimethylene terephthalate) (PTT) biocomposites were prepared by extrusion followed by injection molding machine. The methylene-diphenyl-diisocyanate-polybutadiene (MDIPB) prepolymer was used to enhance the impact strength of the biocomposites. In addition, the polymeric methylene-diphenyl-diisocyanate (PMDI) compatibilizer was used to enhance the mechanical properties of the composites. The effect of compatibilizer on mechanical, crystallization melting, thermomechanical, melt flow index (MFI), morphological, and thermal stability properties of the composites was studied. Thermomechanical properties of the biocomposites were studied by dynamic mechanical analysis (DMA). Scanning electron microscopy (SEM) was used to observe the interfacial adhesion between the fiber and matrix. The results showed that MDIPB and PMDI have a significant effect on the mechanical properties of the composites. The impact strength of MDIPB- and PMDI-compatibilized composites was increased by 87 % when compared to the uncompatibilized composite.