通过熔融缩聚反应对马来酸酐/乙二醇(MA/EG)和四溴邻苯二甲酸酐/乙二醇(TBPA/EG)两个聚酯化反应的动力学进行研究。考察了自催化条件下反应温度、原料配比对聚酯化反应速率的影响。在陈寿安模型的基础上,对反应级数的不同组合进行了比较研究。结果表明:1-1模型和实验结果吻合良好,且kh[H2O]为正值;温度越高,醇酸配比越大,则聚合反应程度越大。
Polyesterifications of ethylene glycol (EG) with maleic anhydride (MA) and tetrabromo phthalic anhydride (TBPA) without foreign acid were carried out under constant reaction temperatures of 162—192℃(rather than at the constant oil-bath temperature) and at different molar ratios of diol to diacid of 1.2—1.8 (MA/EG). The different combinations of the reaction order on the basis of Show-an Chen model were discussed. 1-1 model can describe experimental results very well, andkh[H2O] was greater than zero. The reaction rate constants for both systems were calculated. Besides, It was found that the final COOH conversion was increased with increasing reaction temperatures and molar ratios of diol to diacid.