The kinetics, activation energy, and mechanism of esterification of cotton by mixed polycarboxylic acids, namely, 1,2,3,4-butanetetracarboxylic acid (BTCA) and citric acid (CA), were studied during the curing process of cotton fibers in comparison with the esterification by BTCA alone. The reaction rates of these two polycarboxylic acid finishing systems under different temperatures and the dependency of their reaction rate constants on temperature were studied. Consequently, in the temperature range from 120°C to 180°C, the activation energy of the mixed polycarboxylic acids (BTCA+CA) was obtained as , which was slightly lower than that for the BTCA finishing system. The reaction occurring between the carboxylic acid group of BTCA and the hydroxyl group of CA was proposed. To confirm and prove the speculation, experiments were conducted to investigate the changes in wrinkle recovery angle and tensile strength retention by changing the concentration of both the single polycarboxylic acid and mixed polycarboxylic acids. The results show that, besides esterification of cotton fibers, citric acid probably functioned as an extender in the curing process, when it was combined with BTCA.

中文翻译：

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混合多元羧酸对棉织物进行抗皱整理的机理

比较研究了棉纤维固化过程中1,2,3,4-丁烷四甲酸（BTCA）和柠檬酸（CA）混合多元羧酸对棉花的动力学，活化能和酯化机理。单独用BTCA酯化。研究了这两种聚羧酸精制体系在不同温度下的反应速率及其反应速率常数对温度的依赖性。结果，在120℃至180℃的温度范围内，获得了混合多元羧酸（BTCA + CA）的活化能为，略低于BTCA整理系统。提出了BTCA的羧酸基与CA的羟基之间发生的反应。为了证实和证明这种推测，进行了实验以通过改变单一多元羧酸和混合多元羧酸的浓度来研究皱纹恢复角和拉伸强度保持率的变化。结果表明，当柠檬酸与BTCA结合使用时，除棉纤维的酯化作用外，柠檬酸还可能在固化过程中起到增量剂的作用。