功能单体对聚合物原位处理木材冲击韧性的改善

针对甲基丙烯酸缩水甘油酯(GMA)单体原位聚合处理木材存在脆性较大的缺点,选择具有柔性链段的乙二醇二甲基丙烯酸酯(EGDMA)对之进行增韧改性.采用GMA和EGDMA混合单体溶液浸注木材,再通过加热聚合方式制备木材-GMA-EGDMA复合材料.利用扫描电子显微镜、红外光谱仪和X射线衍射仪观察与分析木材-GMA-EGDMA复合材料的微观形貌、组分特征和聚合物的聚集态;借助冲击韧性试验机测试分析木材-GMA-EGDMA复合材料的冲击韧性.结果表明:GMA+EGDMA单体在木材细胞腔中原位聚合成聚合物,并以无定形态均匀填充木材细胞腔;聚合物与木材基质间存在相对较强的黏结力;聚合物的冲击断面呈典型的韧性断裂特征.木材-GMA-EGDMA复合材料的冲击韧性较木材素材和GMA单体原位聚合处理木材分别提高了98%和220%.

Improvement of Impact Toughness of Polymer in Situ Modified Wood by Functional Monomer

In order to improve the higher brittlement of wood resulted from in situ polymerization of glycidyl methacrylate(GMA), ethylene glycol dimethacrylate(EGDMA) with flexible chain was explored as toughness modifier to treat the wood GMA composite for higher impact toughness. GMA and EGDMA were mixed and impregnated into wood followed by in situ polymerization through heat treatment for the preparation of wood GMA EGDMA composite.The microscopic morphology, component characteristic and polymer aggregation state of wood GMA EGDMA composite were characterized by SEM, FTIR and XRD; and its impact toughness was also analyzed by impact toughness tester.The results indicate that the GMA and EGDMA mixed monomers polymerize into polymer in situ and evenly fill up wood cell lumen pores with amorphous form.The polymer interacts more strongly with wood.And impact fracture of polymer within the wood shows typical ductile fracture characteristic.The impact toughness of wood GMA EGDMA composite is improved by 98% and 220% over wood and wood GMA composite respectively.