Abstract: The cyclic borates were synthesized with the equipment attached to the vac pup, the relations between the structures and the boiling points of the borates were investigated, and the effect of the pH value and the structures on the hydrolytic stability was inspected as well. In the same time, the structures of the products were characterized by the IR， and the performance of the products was tested according to the related GB. The results show that the relations between the structures and the boiling point of the 5-membered ring borates with the side chain of tetraethylene glycol alkyl ether of a given polymerization degree as follows: the bigger of the number ratio of carbon to the oxygen, the lower of the boiling point; the large ring borates as follows: the bigger of the number ratio of carbon to the oxygen, the higher of the boiling point. Finally, the products were prepared of which the dry equilibrium reflux boiling point is above 240 ℃, and the conclusion was acquired that the hydrolytic stability of cyclic borates reaches above 96 h when the pH value of the products is around 7 or above. 

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摘要： 采用减压装置合成环状硼酸酯, 并考察了侧链结构对硼酸酯干沸点的影响, 硼酸酯的pH 值及结构对其水解稳定性的影响。实验利用IR 对产品结构进行表征, 并按照国标方法对硼酸酯的性能进行测定。实验结果表明, 对于五元环状硼酸酯, 一定聚合度的多聚醇醚侧链对硼酸酯的干沸点的影响规律是:侧链的碳氧个数比越大, 其干沸点越低;对于大环硼酸酯:侧链中的碳氧个数比越大, 其干沸点越高。最终, 得到了干平衡回流干沸点在240 ℃ 以上的环状硼酸酯产品, 并且考察出当硼酸酯产品的pH 值至中性或偏碱性时水解稳定性较好, 可达到96 h 以上。

关键词: 环状硼酸酯 , 水解稳定性 , 干平衡回流沸点 , 制动液