挤出成型PP木塑复合材料的力学性能与改性研究

以聚丙烯(PP)为塑料基体,以木粉为填料,并加入添加剂,用挤出成型法制备了PP基木塑复合材料(PP-WPC),研究了增韧剂、相容剂、偶联剂和颜料对WPC力学性能的影响。结果表明:随着增韧剂POE和EPDM加入量的增加,PP-WPC的冲击强度提高,但弯曲强度和弯曲模量有一定程度的降低,其中POE提高冲击强度的效果优于EPDM;适量加入相容剂或偶联剂能提高PP-WPC的弯曲强度和冲击强度,实验条件下相容剂MAPP最佳用量为8%,偶联剂KH570和KH171最佳用量为1%,其中相容剂提高强度的效果显著优于偶联剂;颜料的加入不同程度地降低了PP-WPC的力学强度,其降低程度顺序为:钛白粉>氧化铁黄>氧化铁红>炭黑。

Study on mechanical property and modification of PP wood-plastic composites by extrusion

Polypropylene(PP)/wood plastic composites(PP-WPC)were prepared by extrusion though using PP as a plastic substrate and wood flour as a filler.The influences of the toughening agent,compatibilizer,coupling agent and pigment on the mechanical properties of PP-WPC were investigated.The increase of amount of toughening agents,polyethylene octene(POE) and ethylene-propylene-diene monomer(EPDM) in this report,could significantly improve the impact strength of PP-WPC,however,a negative influences on the flexural strength and flexural modulus were also observed.In comparison to EPDM,POE showed a better performance on toughening of PP-WPC.The mechanical properties of PP-WPC could be improved by using a suitable amount of the compatibilizer(maleated polypropylene,MAPP) or the coupling agent(γ-methacryl oxypropyltrimethoxysilane,KH570 or vinyltrimethoxysilane,KH171).It was found that the mechanical properties were more dependent on the compatibilizer than the coupling agent.The optimum amounts of the compatibilizer and coupling agent were 8% and 1% relative to,respectively.The mechanical strength was reduced by the addition of pigments,in the order of titanium dioxide>yellow iron oxide > red iron oxide> carbon black.