Bronsted-Lewis双酸性离子液体催化合成对苯二甲酸二(二乙二醇丁醚)酯

Synthesis of Di(2-(2-butoxyethoxy)ethanol) Terephthalate by Bronsted-Lewis Acidic Ionic Liquid

摘要:

制备了具有不同SnCl2摩尔分数的Bronsted-Lewis双酸性离子液体3-(1-吡啶基)丙磺酸-氯化亚锡离子液体([3-(1-Py)-(CH2)3-SO3H]Cl-xSnCl2)，x为Lewis所占的摩尔分数。用吡啶探针红外光谱作为表征手段，比较了不同x值催化剂的酸性强度变化，并将其应用于对苯二甲酸二(二乙二醇丁醚)酯的合成反应。考察了x值、原料配比、催化剂用量、带水剂用量、反应时间等因素对酯化率的影响，并对精制产品用1HNMR进行结构表征。结果表明，当x=0.5时，该离子液体的催化活性最高。以[3-(1-Py)-(CH2)3-SO3H]Cl-0.5SnCl2为催化剂，对苯二甲酸(PTA)和二乙二醇丁醚(DGBE)的摩尔配比n(DGBE):n(PTA)=2.3:1，催化剂用量为4.0%(PTA质量)，带水剂正丁醚用量为60.0%(PTA质量)，反应时间为2.5h，搅拌转速300r/min时，产品的酯化率高达99.43%。催化剂在不进行任何处理的情况下，可以循环使用5次。 关键词：双酸性离子液体；对苯二甲酸； 二乙二醇丁醚 ；对苯二甲酸二(二乙二醇丁醚)酯；增塑剂

Abstract:

Bronsted-Lewis acidic ionic liquids [3-(1-Py)-(CH2)3-SO3H]Cl-xSnCl2 wi-th different mole fractions of SnCl2 was prepared(where x is the mole fractio-ns of the Lewis acid).The acidity of the group was characterized and compare-d to each other by means of FTIR in virtue of pyridine molecular probe,the d-ual acidic ionic liquids were then employed to the synthesis reaction of di(2-(2-butoxyethoxy)ethanol) terephthalate.The influences of catalyst type and amount,ratio of reactants,dosage of water-entrainer,reaction temperature,reaction time we-re investigated .In addition,the target product by 1HNMR .The results show that [3-(1-Py)-(CH2)3-SO3H]Cl-0.5SnCl2 had the highest catalytic activity.With [3-(1-Py)-(CH2)3-SO3H]Cl-0.5SnCl2 as catalyst,the optimal reaction conditions were as follows:n(DGBE):n(PTA)=2.3:1,catalyst (4.0% of mass of PTA),water-entrainer (60.0% of mass of PTA),reaction time (2.5h) and the speed stirring was 300r/min.the esterification rate was 99.43%.Catalyst in the case of without any proc-essing, can be recycled five times.