基于SLS快速成形的木塑材料性能的研究

A study of the properties of rapidly-prototyped wood-plastic composites based on SLS

木塑材料的制备借助于碱化、干燥、混合工艺来完成。在成形机上采用SLS技术制作该材料的试件并测试其力学性能和分析扫描电镜SEM的形态。试验结果表明：马来酸酐（MAH）未使用时，随着木粉加入量的增加，复合材料的拉伸模量和弯曲模量都逐渐升高。当使用马来酸酐（MAH）相容剂后，随着其加入量的变化，复合材料的拉伸强度、弯曲强度、冲击韧性和弯曲模量均产生变化，且复合材料的上述值在马来酸酐（MAH）的加入比例为1.5％～2.5％的范围内时达到最高。借助扫描电镜SEM对复合材料断面的分析说明，木塑界面处的机械锚合作用由于马来酸酐（MAH）相容剂的存在得到增强，从而提高了木塑材料的力学性能。

Materials for polypropylene/wood-powder composite are prepared in the way of alkalization , drying and mixing .Test pieces or specimens are made in the shaper with selective laser sintering before their mechanical properties are to be tested or measured and an analysis made of them with scanning electron microscope （SEM） .The experimental findings show that before the use of MAH both the tensile strength and flexible strength are lower than those of the pure polypropylene （PP）when wood powder is filled into polypropylene ,whereas both its tensile modulus and flexible modulus gradually rise with the increase in the content of wood powder .When MAH is used as the compatibilizer ,the tensile strength , flexible strength ,impact strength and flexible modulus of the wood-plastic composite with higher wood powder mass fraction of 40% vary with the changes of MAH contents ,and when the contents of MAH fall into the range from 1.5% to 2.5% ,the above values of the composite are normally the highest .SEM photos of the fractured surface of the composite show that the existence of compatibilizer not only strengthens the interaction between wood powder and the base material ,but also influences the mechanical anchorage on the interface of the wood powder and the base material ,which is helpful to the improvement of the mechanical properties of the composite .