用差示扫描量热法(DSC)对固态条件下聚酯/TGIC (triglycidyl isocyanurate)体系的非等温固化反应动力学进行了研究.根据DSC和热重(TG)的分析结果,对聚酯粉末的固化过程及热稳定性进行了探讨,通过温度-升温速率图外推法确定了该体系的凝胶温度、固化温度和后固化温度分别为113、146和195℃.采用Kissinger方程、Doyle-Ozawa方程和Crane方程对DSC数据进行分析,得到了固化反应的平均表观活化能65.71 kJ·mol-1,频率因子8.50×106 min-1、反应级数0.95,建立了该树脂体系的固化动力学模型.讨论了固化反应速率、固化度、固化温度与时间等关系的变化规律及影响因素,为优化铝型材用粉末涂料聚酯体系的固化工艺提供了理论基础.%The non-isothermal/TGIC curing kinetics of powder coating of polyester resin was investigated by differential scanning calorimetry (DSC). The curing process and thermal stability of this powder coating system were discussed based on the DSC and thermogravity ( TG) results. The gelation temperature, curing peak temperature, and post-cure temperature were respectively calculated to be 113, 146 and 195°C from the non-isothermal DSC results by extrapolating the graph of temperature versus heating rate. The DSC data were analyzed with the Kissinger, Doyle-Ozawa and Crane equations, and the curing kinetic model of the powder coating system was established. The kinetic parameters, including the apparent activation energy, frequency factor and order of reaction were estimated to be 65. 71 kj ? Mol'1 , 8. 50X 106 min"1 and 0.95, respectively. The influence factors of curing reaction rate, degree of cure, curing temperature and time were discussed. This study provides a theoretical basis to understand and optimize the curing process of powder coating of polyester resin for aluminum electrostatic powder spraying.
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