光纤用丙烯酸基蓖麻油氨基甲酸酯齐聚物的合成反应

Synthetic Reaction of Castor Oil-Urethane Acrylate Oligomers for Optical Fibers

丙烯酸羟乙酯与2,4-甲苯二异氰酸酯(2,4-TDI)缩合生成丙烯酸基单异氰酸酯,及其随后加入蓖麻油扩链,生成丙烯酸基蓖麻油氨基甲酸酯齐聚物(VTPU)的合成反应均为二级反应。由求得的反应速率常数(K_P)和表观活化能(E_a)数据表明:利用2,4-TDI中两个异氰酸基在不同温度下的反应活性差别,采用分步法,有利于合成分子结构规整性好的VTPU产物。该产物与丙烯酸酯稀释和光敏剂组成的紫外光固化无溶剂涂料,能满足光纤应用的要求。

It was found that the reaction of 2,4-toluene diisocyanatc (2,4-TDI) and hydroxyethy acrylate (HEA) forming ITP is a second reaction, and so is the reaction of ITP with castor oil (CAS) forming VTPU, From the rate constant (k_p) and apparent activity energy (E_a) of the reactions, the product VTPU with regular structure can be modulated by using the difference of reactivity between the pare- and orth- NCO in 2,4-TDI at different temperature with two-step reactions. The solvent-free paint consisting of VTPU, acrylic diluents and photoinitiator cured by ultraviolet radiation was satified for optical fibers fabrication.