Preparation And Performance Research For Wood Flour Filled Polypropylene

In this paper, PP and wood fiber with 80 meshes were blended to prepare for PP/WF Composites by twin-screw extruder. Research was focused on the effect and mechanism of wood flour content, different kinds of compatibilizers with differential content, alkali treatment on wood flour and OMMT to PP/WF Composites. Research shows that more wood flour content brings weaker mechanical properties, decreased thermostability, higher water absorption rate, and poorer melt fluidness. Three maleated compatibilizers were used in this paper to improve the surface bonding of PP and wood flour. PP-g-MAH exhibits the most obvious compatibilization effect in this system and mechanical properties reached to the highest level at 10% point that tensile strength increased by 40.9%, flexural strength increased by 47.3% and flexural modulus increased by 35.3%. Adding of PP-g-MAH also brings PP/WF composites faster crystallization rate, higher crystallization degree and better thermostability. Alkali treatment for wood flour by 18wt% NaOH will improve mechanical properties and melt fluidness of PP/WF composites. Intercalation will be produced if OMMT was added in PP/WF system, which can improve mechanical properties and thermostalbility of composites. Part of polar anhydride group of maleated compatibilization will yield esterification reaction with hydroxyl group of wood flour, another part will form hydrogen bond with hydroxyl group of wood four. And non-polar long chain part of maleated compatibilizer has good compatibilization effect with PP. Above factor combine PP and wood flour together. Alkali treatment will remove foreign matter, ash on surface of wood flour, increase touch surface between PP and wood flour, improve surface bonding from physical method.As above description, PP/WF composite will be prepared by thermo-melt-molded machine after adding proper treatment on wood flour or right compatibilizer. Natural fiber as filler of wood-plastic composites meet requirement of resource saving and environment protection, and exist huge marketing value and development prospect.