Effects of chemical treatment on wood fiber reinforced recycled Polypropylene composites

Abstract

The surface of wood fiber (WF) used as reinforcement in recycled polypropylene/wood fiber (rPP/WF) composites was modified by silane coupling agent. The effect of filler loading and silane as coupling agent on mechanical, morphological and thermal properties was investigated. The composites were prepared by using Twin Screw Extruder at processing temperature 200 ºC and screw speed of 75 rpm. The results indicated that the increasing of filler loading increased Young’s modulus but reduced the tensile strength and elongation at break. However, the presence of silane coupling agent have slightly increased the tensile strength and elongation at break but decreased Young’s modulus of treated composites compared to untreated composites. The scanning electron microscope (SEM) micrograph of tensile fracture surfaces showed that the treated rPP/WF composites showed better filler dispersion in matrix and embedded filler into the matrix compared to untreated rPP/WF composites. The addition of silane as coupling agent enhanced the interfacial adhesion between matrix and filler which leads to better properties of rPP/WF composites. Moreover, the micrograph for treated rPP/WF composites with 3-aminopropyltriethoxysilane (3-APE) shows the smoother surfaces compared to untreated rPP/WF composites. The changes of functional group of untreated and treated rPP/WF composites were proven by the FTIR observation.