微波辅助离子液体制备及催化降解聚酯

Synthesis of Ionic Liquid and Glycolysis of PET by Microwave-assisted Method

采用微波辅助离子交换法,以氯化1-丁基-3-甲基咪唑([Bmim]Cl)和氯化锌为原料,合成了1-丁基-3-甲基咪唑氯锌酸盐离子液体,并考察了合成过程中溶剂对离子液体合成的影响。进一步以制备的离子液体为催化剂,乙二醇为溶剂,采用微波辅助乙二醇醇解聚对苯二甲酸乙二醇酯(PET)。以对苯二甲酸的回收量为指标,分别考察了离子液体用量、反应温度、时间以及溶剂用量对PET降解反应的影响。结果表明,采用微波辅助离子交换法在30 min内即可合成得到相应的离子液体,以二氧六环为溶剂时,3种产物的产率均高于90%。在微波加热的条件下,离子液体[Bmim][Zn2Cl5]对PET的乙二醇醇解反应具有较好的催化性能,对苯二甲酸的产率超过20%。

Using microwave-assisted ion-exchange method,several kinds of ionic liquids of 1-butyl-3-methylimidazolium zinc chloride were synthesized from the raw materials of 1-butyl-3-methylimidazolium chloride and zinc chloride.The influence of solvents on the synthesis of ionic liquid was also investigated.The glycolysis of poly（ethylene terephthalate） by microwave-assisted method using the synthesized ionic liquids as catalysts and glycol as solvent was also studied.The influence of the dosage of ionic liquid,reacting temperature,reacting time and dosage of solvent on the glycolysis of PET was studied based on the indicator of the yield of recovered terephthalic acid.The results show that the corresponding ionic liquids could all be synthesized within 30 mins by microwave-assisted ion-exchange method.The yields of the three kinds of ionic liquids were all more than 90% when dioxane was used as solvent.[Zn2Cl5] exhibited higher catalytic activity for the glycolysis of PET by microwave-assisted method.The recovery yield of terephthalic acid was more than 20% by using [Zn2Cl5] as catalyst.