High density polyethylene composites reinforced with bmimcl-and ctab-treated sawdust: Structural and mechanical properties.

Abstract

The successful interactions between the sawdust and matrix are among the significant factors determining the strength and durability of wood-plastic composites (WPCs). This work aims to evaluate the structural and mechanical properties of high-density polyethylene (HDPE) composites reinforced with sawdust pretreated with ionic liquids 1-butyl-3-methylimidazolium chloride (BMIMCl) followed surface modification by cationic surfactant, n-hexadecyl trimethylammonium bromide (C16H33N(CH3)3Br, (CTAB). The chemical and structural properties of raw and pretreated sawdust were analysed using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD). The morphology of the sawdust was observed using field emission scanning electron microscopy (FESEM). After sawdust analysis, the raw and pretreated sawdust was mixed into the HDPE, in a proportion of 30/70 wt% using a single screw extruder followed by injection moulding. Furthermore, the specimens for tensile and flexural testing was prepared to evaluate the mechanical properties. The fractured surface of the composites was also analysed using FESEM. The results showed that the pretreatment with BMIMCl and CTAB had improved the crystallinity and functionalisation of CTAB into sawdust structure. The mechanical results showed that the composites reinforced with BMIMC-and CTAB-treated sawdust showed only an improvement in elongation but did not improve tensile and flexural strength.