木粉、废旧橡胶和高密度聚乙烯复合材料的 热解动力学特性

将木粉、高密度聚乙烯(HDPE)与不同含量的废旧橡胶粉复合制备木橡塑复合材料,采用热重分析法(TGA)研究各组分材料及复合材料的热解动力学特性,并引入Flynn-Wall-Ozawa模型量化了组分及复合材料的表观活化能。结果表明:木粉、HDPE、废旧橡胶粉复合材料(WRPC)的热解出现两个显著的失重区(230～380 ℃和430～580 ℃),分别对应木粉/废旧橡胶和HDPE的热降解。木粉、废旧橡胶和HDPE热解过程平均活化能值分别为179.2、243.8和246.8 kJ/mol,WPC(木粉、HDPE复合材料)平均活化能为239.3 kJ/mol,WRPC活化能值较WPC低(200.3～208.4 kJ/mol)。活化能的变化表明木、橡、塑3种原料在复合材料的热解过程中具有协同效应,而废旧橡胶的掺入对复合材料的热降解特性发挥了显著的调控作用。

Thermal decomposition kinetics of wood/rubber/HDPE composites

Wood-waste rubber-HDPE composites(WRPC)were made with different rubber content. Thermogravimetric analysis(TGA)method was applied to investigate the thermal decomposition kinetics of wood flour, HDPE, waste rubber, WPC, and WRPC. The corresponding apparent activation energy(AAE)values were calculated with the Flynn-Wall-Ozawa model. The results showed that WRPCs have two weight loss stages at 230-380 ℃ and 430-580 ℃ due to thermal decomposition of wood/rubber and HDPE, respectively. The AAE values for wood, waste rubber, HDPE were 179.2, 243.8, 246.8 kJ/mol, respectively, while 239.3 kJ/mol for WPC. Decreased AAE values were found for WRPCs, i.e., 200.3-208.4 kJ/mol. It's concluded that the three raw materials, i.e., wood, rubber, and HDPE, synergistically react in WRPC decomposition process, and rubber addition content has evident influence on the thermal decomposition behaviors of WRPC.