离子聚合物增容增韧木塑复合材料的研究

Effect of Ionomer on Compatibilization and Tonghing of Wood/PE-HD Composites

为了提高木塑复合材料(WPC)的相容性和冲击韧性,利用哈克微量混合流变仪制备木粉/高密度聚乙烯(PE-HD)/钠离子聚合物复合材料,研究钠离子聚合物对WPC增容增韧的影响。结果表明,当木粉质量分数为40%时,添加质量分数为4%的钠离子聚合物,WPC的拉伸强度是添加质量分数为4%的马来酸酐接枝聚乙烯(PE-g-MAH)的WPC的1.7倍,钠离子聚合物对提高WPC的冲击韧性有突出贡献;添加钠离子聚合物的WPC的线性热膨胀系数(LTEC)稍微低于添加传统PE-g-MAH的WPC的LETC,表明钠离子聚合物可以限制复合材料的热膨胀,但是效果并不明显;傅立叶变换红外光谱图谱发现,添加钠离子聚合物的WPC接入了羧基基团,表明钠离子聚合物和木纤维发生了化学反应,增强了WPC的界面强度;通过扫描电子显微镜观察WPC的表面和断面形貌,发现添加钠离子聚合物后,PE-HD对木粉有很好的包覆效果,没有明显的界面缝隙。

In order to improve the compatibility and impact toughness of wood plastic composite（WPC）, the wood flour / high density polyethylene（PE-HD） / sodium ionomer composites were prepared by extruding mold with HAAKE minilab, and the effect of sodium ionomer on compatibilization and toughing of WPC were investigated. The results show that when the mass fraction of wood flour is 40%, the tensile strength of WPC with 4% of sodium ionomer mass fraction is 1.7 times of that with 4% of maleic anhydride grafted polyethylene（PE-g-MAH）, and sodium ionomer makes outstanding contributions to increase the impact toughness of WPC ; the linear thermal expansion coefficients（LTEC） of WPC by adding sodium ionomer is slightly less than that with traditional PE-g-MAH, which indicates sodium ionomer can restrict thermal expansion ofWPC, but the restriction effect is not very obvious ; Fourier transform infrared spectroscopy spectrum shows WPC by adding sodium ionomer has carboxyl group which indicates sodium ionomer and wood fibre produce chemical reaction and increase the interfacial strength ; The surface and fracture surface morphology of WPC were analyzed by scanning electron microscope , the good coating effect of PE-HD on wood flour can be observed, and no clear interface gaps are found.