Effect of Fiber Surface Modification with Different Functional Groups Silane Agents on Mechanical Properties of Hemps/Polypropylene Composites

International audienceIn this paper, we firstly treated the hemp fiber with alkali solution, followed by chemical modification with silane agents: 3-(Trimethoxysilyl) propyl methacrylate (MPS), N-[3-(Trimethoxysilyl) propyaniline (PAPS) and (3-Aminopropyl) triethoxysilane (APS), respectively. These treated fibers were then blended with polypropylene (PP). SEM morphology and FT-IR spectra confirmed the successful modifications of MPS, PAPS and APS with hemp fiber. The tensile tests results showed that APS improved the mechanical properties of composite, due to the amino of APS could react with maleic anhydride forming amide covalent bond which is benefit in the stress transferring from PP matrix to fiber. In contrast, since the incompatibility of aniline with propylene, PAPS modification decreased the fracture stress composites. The existences of ester and vinyl groups in MPS contributed to the increase of composite fracture strain caused by chain slips