熔融酯化法合成马来酸单聚乙二醇单甲醚酯工艺研究

Synthesis of maleic acid mono polyethylene glycol mono methyl ether acetate by melt esterificatin

以马来酸酐(MAH)和聚乙二醇单甲醚(MPEG)为原料,以对甲苯磺酸为催化剂,采用熔融酯化法合成了马来酸单聚乙二醇单甲醚酯(MPEGMA)。利用红外光谱分析了温度对MPEG与催化剂混合物稳定性的影响规律,考察了单体摩尔比、催化剂用量以及反应时间等条件对酯化率的影响,并通过红外光谱分析表征了酯化产物的结构。试验结果表明:当n(MAH∶)n(MPEG)=1.2∶1,催化剂用量为聚乙二醇单甲醚和马来酸酐(MAH)总质量的1%,控制反应温度在110℃,反应时间为6h时酯化率可达到83.7%,酯化产物双键结构的红外特征峰明显。

Maleic acid mono polyethylene glycol mono methyl ether acetate（MPEGMA） was synthesized by melt esterification of maleic anhydride（MAH） and polyethylene glycol single methyl ether（MPEG） as raw materials in the presence of p-toluene sulfonic acid as catalyst.Effect of temperature on stability of admixture of MPEG and activator was discussed by FT-IR.And the influence of molar ratio of monomer,dosage of catalyst and reaction time on the esterification were investigated.Double-bond stretching vibration band in esterification product was characterized by Fourier transform infrared spectroscope（FT-IR）.The results showed that the optimum reaction condition is as follows：the molar ratio of MAH to MPEG is 1.2∶1,mass fraction of catalyst is 1% to the total MAH and MPEG,reaction temperature is 110 ℃,reaction time is 6 h.Under this condition,the esterification rate could reach 83.7% and the double-bond stretching vibration band of the product was significant.