聚乙烯热熔胶增容聚乙烯基木塑复合材料的研究

采用废木粉和高密度聚乙烯制备复合材料,并采用一种聚乙烯热熔胶作为相容剂以增进憎水性的聚乙烯基材和亲水性的木粉界面的相互作用。评价了该热熔胶的增容效果,并对其增容机理进行了详细论述。研究结果表明:该热熔胶的主要成分为马来酸酐接枝高密度聚乙烯(PE-HDg-MAH)和乙烯-醋酸乙烯酯共聚物(EVA);添加木粉有利于弯曲强度和弯曲模量的提高,但使冲击强度和拉伸强度迅速下降;该热熔胶可明显提高复合材料的力学性能,并且木粉的填充量越高,则增容作用就越明显;当木粉的用量为50％时,使用该热熔胶可使复合材料的拉伸强度、弯曲强度、弯曲模量和冲击强度分别提高115．6％、66．7％、38．1％和67％;基于这些结果可知,该热熔胶可显著提高聚乙烯基材／木粉界面处的亲和力,是聚乙烯基木塑复合材料理想的增容剂。

Study on PE Based Wood-plastic Composite Compatibilized by PE Hot Melt Adhesive

A polyethylene hot melt adhesive was used as a compatibilizer in a composite of wood flour and polyethylene. The compatibilizing mechanism of this hot melt adhesive was explored. IR spectrum showed that the hot melt adhesive is composed mainly of maleic anhydride grafted high-density polyethylene (PE-HD-g-MAH) and ethylene/vinyl acetate copolymer (EVA). The addition of wood flour increased the flexural strength and modulus of PE-HD, but decreased sharply the tensile and impact strength. However, the hot melt adhesive enhanced the mechanical properties of the composite considerably. The higher the wood flour content was, the more remarkably the compatibilizing effect of the hot melt adhesive exhibited. When the content of wood flour was 50 % , an adequate amount of the hot melt adhesive may increase the tensile strength, flexural strength, flexural modulus, and impact strength of the composite by 115. 6 % , 66. 7 % , 38.1 % , and 67 % ,respectively, based on devoid system. It was concluded that the hot melt adhesive enhanced the interfacial affinity between polyethylene matrix and wood flour, and thus constituted an excellent compatibilizer.