空气中PE-LD与PE-LD-g-HEA的非等温热分解行为研究

采用固相接枝法制备了丙烯酸-2-羟乙酯（HEA）接枝低密度聚乙烯（PE-LD）共聚物（PE-LD-g-HEA），通过X射线衍射仪、傅里叶红外光谱仪分析了不同温度处理下PE-LD、PE-LD-g-HEA的结构变化，并用热重分析法研究了二者的热分解动力学。结果表明，热处理时PE-LD-g-HEA较PE-LD的结晶度变化小，主链断裂缓慢，热稳定性提高；Kissinger法和Crane法计算了PE-LD表观活化能为88.63 kJ/mol、指前因子1.17×106 s-1、反应级数为0.88，接枝产物的表观活化能为217.35 kJ/mol、指前因子5.92×1015 s-1、反应级数为0.95，Ozawa法计算的表观活化能值与Kissinger法相相近。

Non-isothermal Decomposition Behavior of PE-LD and PE-LD-g-HEA in Air

Low density polyethylene (PE-LD) was grafted with 2-hydroxyethyl acrylate (HEA) forming a copolymer (PE-LD-g-HEA) by solid phase method. The structure of the PE-LD and PE-LD-g-HEA during aging treatment at different temperatures in air was studied using X ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR), and the thermal decomposition kinetics was studied by thermogravimetry. Because PE-LD-g-HEA had more long chain branches than PE-LD, its crystallinity was less influenced by aging treatment, the main chain was less scissored, and the thermal stability was better than PE LD. The apparent activation energy, pre exponential factor, and reaction order were determined by Kissinger and Crane methods were 8863 kJ/mol, 1.17×106 s-1 and 0.88 for PE-LD, and 217.35 kJ/mol, 5.92×1015 s-1 and 0.95 for PE-LD-g-HEA, respectively. The value of the apparent activation energy determined by Ozawa method was close to that by Kissinger method.