丁酮肟封闭多亚甲基多苯基多异氰酸酯的研究

以丁酮肟为封闭剂,制备了封闭型多异氰酸酯树脂;通过实验,讨论了丁酮肟与异氰酸酯基团的摩尔比、反应温度、反应时间对封闭反应的影响;并通过红外光谱研究了封闭产物解封温度。结果表明,最佳反应条件为n(丁酮肟)/n(-NCO)为1.2,反应温度60℃,反应3 h,且封闭物在120℃左右可以解封。

Study on Polyaryl Polymethylene Isocyanate Blocked by Diacetylmonoxime

Blocked polyisocyanate were synthesized with diacetylmonoxime as blocking agent. The influence of the molar ratio, reaction temperature and time of blocking reaction were discussed by experiment. The deblocking temperatures of blocked isocyanate were researched by the infrared spectra. The results showed that the optimum reaction condition was obtained when the mole ratio of the diacetylmonoxime to the polyisocyanates was 1.2, the reaction temperature was 60 ℃, and the reaction time was 3 h. The deblocking temperature was 120 ℃.