KEVLAR PULP-THERMOPLASTIC ELASTOMER COMPOSITES: MORPHOLOGY AND MECHANICAL PROPERTIES

Abstract

Reinforcement of Styrene (Ethylene Butylene) Styrene thermoplastic elastomer (SEBS) with Kevlar pulp was investigated. Surface treatment of the fibre was carried out by alkali hydrolysis in order to increase the number of reactive groups. Maleic anhydride-grafted-SEBS was used as a compatibiliser. The composites were prepared by a one step process in an internal mixer. Mechanical properties of the composites were assessed using a tensile testing machine. The results suggested that as the loading of Kevlar pulp increased, tensile modulus increased but tensile strength and elongation at break decreased. The fracture surface of the composites observed under Scanning Electron Microscope (SEM) revealed fibre pull-out in the composite without compatibiliser and more fibre breakage were observed in the samples containing compatibiliser. Quantitative analysis of the adsorbed elastomer on the fibre surface using gravimetric, diffuse reflectance FTIR (DRIFT) techniques and observation of SEM micrographs of extracted pulp showed that in the presence of compatibiliser, a large amount of elastomer was adsorbed. However, SEBS-g-MA showed no remarkable effect on the tensile properties of the composites and this might be due to uneven adsorption of rubber particles.