木粉接枝甲基丙烯酸甲酯/丁酯及其在木粉/PVC复合材料中的应用

Graft Polymerization of MMA/BMA on Surface of Wood Powder and Its Application in PVC Composite Materials

用一定pH值的KH-570水溶液对木粉进行偶联处理,然后在紫外光作用下,引发甲基丙烯酸甲酯/甲基丙烯酸丁酯(MMA/BMA)在木粉表面进行接枝共聚,考察偶联剂用量及溶液pH值、引发剂(BPO)用量、两种单体总量及配比对木粉接枝率的影响,同时考察处理前后木粉填充PVC复合材料的力学性能,并采用扫描电镜对复合材料的断口形貌进行分析.结果表明:偶联剂用量及溶液pH值、接枝单体MMA、BMA用量及配比均对木粉接枝率有显著影响,在最佳配比条件下木粉最高接枝率可达32%.与未改性的木粉相比,接枝改性后的木粉填充PVC复合材料的力学性能显著提高,其拉伸强度和冲击强度可分别提高90.3%和25.3%,扫描电镜照片显示木粉分散更均匀,界面结合良好.

Wood powder was treated by coupling agent-KH-570 dissolved by diluted acid with certain pH. Then the graft copolymerization of MMA/BMA has been carried on the surface of wood powder by UV initiation. The graft conditions such as pH of diluted acid concentrations, the content of KH-570, the content of initiator BPO, the content of monomers, and the ratio of two kinds of monomer. And its application in PVC composite materials was investigated. The effects of the mechanical properties of composites with wood powder/PVC were studied. And the micro-morphology of composites were studied by Scanning Electron Microscopic（SEM）. The results showed that： Different graft conditions have great effect on the graft yield（G）, and G is 32 % at the best graft conditions. Meantimes wood powder modified by the graft copolymerization of MMA/BMA improved greatly the mechanical properties of composites with wood powder/PVC. The tensile and impact strength of the composite material of PVC/wood powder grafted with PMMA/PBMA were increased about 90.3 % and 25.3 % respectively than that of the composite material of PVC filled with wood powder not modified. And SEM examination revealed good dispersion , and the surface of wood powder and PVC have good adhensive.