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利用热重（TG）分析技术研究了端羟基超支化聚酯（HBP）以及十八酸改性的超支化聚酯（MHBP）的热失重行为,运用Flynn-Wal-l Ozawa法和Coats-Redfern法对非等温热分解动力学数据进行了分析。结果表明,HBP的分解过程分为三个阶段,三个阶段的表观活化能分别为120.238 kJ/mol、149.775 kJ/mol、173.540 kJ/mol,指前因子分别为1.386×10^9min^-1、1.341×10^9min^-1、4.569×10^12min^-1;MHBP的分解过程仅有一个阶段,表观活化能和指前因子分别为204.275kJ/mol和2.417×10^14min^-1。超支化聚酯的热稳定性与其端基有关,十八酸改性的超支化聚酯由于长链烷烃具有结晶性,因而热稳定性优于端羟基超支化聚酯。

The pyrolysis characteristics of hydroxyl-terminated hyperbranched polyester（HBP） and hyperbranched polyester modified with stearic acids（MHBP） were studied by thermogravimetric analysis technology（TG）.The mechanism functions were identified with the kinetic parameters obtained from the analysis of TG curves by Flynn-Wall-Ozawa method and Coats-Redfern method.The results show that the decomposition process of HBP is composed of three stages.The apparent activation energie of these three stages is 120.238kJ/mol,149.775 kJ/mol,173.540 kJ/mol,respectively.The pre-exponential constant is 1.386×109min-1,1.341×109 min-1,4.569×1012 min-1,respectively.The decomposition process of MHBP is composed of only one stage.The apparent activation energy and the pre-exponential constant is 204.275 kJ/mol and 2.417×1014 min-1,respectively.The thermostability of hyperbranched polymers relates with the terminal groups.Compared with hydroxyl-terminated hyperbranched polyester,hyperbranched polyester modified with stearic acids has better thermostability due to its crystalline long alkyl chains.