[Bmim]BF_4/p-TSA催化合成聚甲基膦酸乙二醇酯

Synthesis of Poly(oxy-1,2-ethanediyl) methylphosphonate Catalyzed by [Bmim]BF_4/p-TSA

以甲基膦酸二甲酯（DMMP）和乙二醇（EG）为原料，离子液体[Bmim]BF4与对甲苯磺酸（p—TSA）为协同催化剂，合成了一种阻燃剂聚甲基膦酸乙二醇酯。通过正交实验L9（3’），确定最佳合成条件为：n（DMMP）：n（EG）=1：1；催化剂总用量为DMMP物质的量的3％，其中[Bmim]BF4占1％，p-TSA占2％；反应温度为155—170℃；反应时间为4h。产物为淡黄色透明黏稠液体，酸值370mgKOH／g。用红外光谱表征了产品结构；用液质分析了产品组成为十几种不同程度的乙二醇甲基膦酸二甲酯聚合物；用气质分析了副产物组成主要为甲醇、甲醚、乙二醇单甲醚、乙二醇二甲醚和二缩乙二醇。

Using dimethyl methylphosphonate （DMMP） and ethylene glycol （EG） as raw materials,p- toluenesulfonic acid （ p-TSA ） and 1-butyl-3-methylimidazolium tetrafluoroborate （ [ Bmim ] BF4 ） as synergetic catalysts, a novel polyphosphonate flame retardant was synthesized in a distillation apparatus. The molar ratio of raw materials, the amount and molar ratio of catalysts and reaction temperature were investigated by L9 （33） orthogonal experiment. The optimal synthesis conditions were as follows：the molar ratio of EG to DMMP being 1：1 ,n（ [ Bmim] BFn）/n（DMMP） =0. 01 ,n（p-TSA）/ n（DMMP） =0.02 ,the reaction temperature 155 - 170 ℃ ,and reaction time 4 h. The synthetic product was yellowish transparent liquid and its acid value was 370 mg KOH/g. The product was characterized by IR and LC-MS analysis and the results showed that the product is a mixer of different polymers. The composition by side reactions which are mainly methanol, dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether and ethylene glycol reduction were characterized by IR and GC- MS analysis.