Surface Modified Abaca Fibers: Physico-Mechanical, Morphological and Degradation Properties Evaluation

Haydar Zaman; Ruhul A. Khan

Abstract

Lignocellulosic fibers are used as cost-cutting fillers in plastics factories. Amid several factors, the ultimate performance of composite ingredients depends on the bond between the matrix resin and the filler, and hence on the quality of the interface. To acquire optimal performance of the end product, adequate interaction between the matrix and the lignocellulosic ingredient is preferred. This is often acquired through surface modification of the matrix or filler. Abaca fiber (AF), a lignocellulosic fiber derived from the pseudo-stem of the abaca plant (Musaceae family), is a bast fiber with relatively good mechanical features. AFs were irradiated with ultraviolet (UV) radiation at different intensities and then AF/PP unidirectional composites (40 wt% by fiber) were fabricated by compression molding. It was observed that the mechanical features of irradiated AF/PP composites were significantly improved compared to non-irradiated counterparts. To increase these features, the surfaces of irradiated AFs were modified with dissimilar concentrations of 2-hydroxyethyl methacrylate (HEMA) in methanol and cured under UV radiation. The grating and mechanical features were optimized and recorded, and the tensile strength, tensile modulus and impact strength values were increased by 25%, 22% and 30%, respectively, compared to the non-irradiated AF/PP composites. The surfaces of AFs were left in alkali (NaOH) solution with several concentrations for half an hour to modify them. AFs were then grafted with optimized HEMA solution and photocured under the similar UV light. The grafting of alkali treated AF (AAF)/PP composites exhibited the best mechanical features than optimized HEMA treated composite sample. SEM studies showed that the optimized alkaline + optimized HEMA treated AF/PP composite had better dispersion than the optimized HEMA treated AF/PP composite. Moisture absorption and simulating weathering analysis of the composites were also examined.