Polypropylene-Wood Fiber Composites: Effect of Fiber Treatment on Mechanical Properties

Abstract

Polypropylene (PP) was reinforced with different wood fibers, chemithermomechani-cal (CTMP) aspen and commercial pulps (Tempure and Temalfa-A). Various chemical treatments on the fiber was carried out to improve the bonding at the interface. Fibres coated with Silane coupling agents Silane A-172 and A-174 (with vinyl and methacryloxy functional groups respectively) upon reinforcement showed poor tensile strength. PP filled with Pre-coated fibers containing maleated propylene wax, polymer and polymethylene polyphenyl isocyanate produced higher tensile strength and modulus. The use of dicummyl peroxide and cummine hydro peroxide as initiators during the coating of the fiber was not effective. Polypropylene reinforced with fibers of lower mesh size gave better tensile properties.