【作者】 崔晓；

【导师】 刘福胜；

【作者基本信息】 青岛科技大学 ， 化学工艺， 2009， 硕士

【摘要】 本文首先设计并合成了不同类型的离子液体,考察了离子液体对聚酯树脂（PET）的溶解情况,然后以离子液体为反应介质和催化剂,对PET分别进行了水解、甲醇醇解及辛醇醇解反应研究。考察了离子液体种类、反应时间、反应温度、催化剂用量、水（或醇）用量及溶剂用量对降解反应结果的影响。另外,对离子液体的重复使用性能进行了研究,并采用红外光谱对所得的各种降解产品进行了表征。设计合成了20余种不同类型的离子液体,采用FT-IR和NMR.技术对部分离子液体结构进行了表征。考察了离子液体种类、温度与时间对PET溶解性能的影响。结果表明,氯化1-丁基-3-甲基咪唑离子液体溶解效果最佳,在130℃,8h溶解度可达15.3g。对PET在离子液体环境下的水解反应进行了研究,考察了离子液体种类、反应温度、反应时间、溶剂型离子液体用量及催化剂型离子液体用量对PET水解反应结果的影响。结果表明,性能较好的溶剂型离子液体为氯化1-丁基-3-甲基咪唑（[Bmim][Cl]）,催化剂型离子液体为1-甲基-3-（3-磺酸基丙基）咪唑硫酸氢盐（[HSO₃-pmim][HSO₄]） ,较佳工艺条件为m（PET）:m（H2O）: m（[Bmim][Cl]）:m（[HSO₃-pmim][HSO₄]）=3:4:6:0.6,反应温度170℃,反应时间4.5h。在上述条件下,PET降解率100%,产品对苯二甲酸收率大于88%。离子液体重复使用8次后,PET降解率和对苯二甲酸收率无明显降低。对PET在离子液体环境下的甲醇醇解反应进行了研究,考察了离子液体种类、反应温度、反应时间、溶剂型离子液体用量、催化剂用量及甲醇用量对PET甲醇醇解反应结果的影响。结果表明,性能较好的溶剂型离子液体为[Bmim][Cl],较佳工艺条件为m（[Bmim][Cl]）:m（PET）=2:1,m（甲醇） :m（PET） =4:1,醋酸锌占反应液5%,反应温度160℃,反应时间3.0h。在上述条件下,PET降解率100%,产品对苯二甲酸二甲酯的收率88%以上。离子液体重复使用8次后,PET降解率和对苯二甲酸二甲酯的收率无明显降低。对PET在离子液体环境下的辛醇醇解反应进行了研究,考察了反应时间、原料配比、溶剂型离子液体和催化剂用量对PET辛醇醇解反应结果的影响。结果表明,较佳工艺条件为反应温度为回流温度,m（[Bmim][Cl]）:m（PET）=2:1,n（异辛醇）:n（PET）=3:1,醋酸锌占PET 1%,反应时间3.5h。在上述条件下,PET降解率可以达到100%,产品对苯二甲酸二（2-乙基己）酯收率可达到90%以上。离子液体重复使用8次后,PET降解率和产品的收率无明显降低。有关PET在离子液体条件下的化学降解反应研究目前未见文献报道。更多还原

【Abstract】 In this paper, different kinds of ionic liquids were designed and synthesized and the dissolubility of poly（ethylene terephthalate） （PET） in ionic liquids was studied. Hydrolysis, methanolysis and 2-ethylhexanolysis of PET were investigated using ionic liquids as reaction media and catalyst. Moreover, the effects of kinds of ionic liquids, reaction time, reaction temperature, amount of catalyst, dosage of water or methanol and dosage of solvent on depolymerization of PET were examined respectively. The reusable performances of ionic liquids were also examined and the obtained products were characterized by FT-IR.Over 20 different kinds of ionic liquids were synthesized and parts of them were characterized by FT-IR and NMR. Moreover, the effects of kinds of ionic liquids, temperature and time on dissolution of PET in ionic liquids were examined. It was showed that ionic liquid 1-butyl-3-methylimidazolium chloride （[Bmim][Cl]） was of good solubility. Under the conditions of temperature 130℃and time 8h, the dissolubility of PET could reach up to 15.32g.The hydrolysis of PET in ionic liquids was studied using ionic liquids as reaction media and catalyst. The effects of kinds of ionic liquids, reaction temperature, reaction time, dosages of solvent and catalyst on hydrolysis result were examined. It was showed that [Bmim][Cl]) was a suitable solvent and 1-methyl-3-（3-sulfopropyl）- imidazolium hydrogen sulfate （[HSO₃-pmim][HSO₄]） was a good catalyst. The obtained optimum reaction conditions were reaction temperature170℃,m（PET）:m（H2O）:m（[Bmim][Cl]）:m（[HSO₃-pmim][HSO₄]）=3:4:6:0.6, reaction time 4.5h. Under above conditions, the conversion of PET and the yield of terephthalic acid were 100% and >88% respectively. The ionic liquids could be reused 8 times without obvious decrease in the conversion of PET and yield of terephthalic acid.The methanolysis of PET in ionic liquid was studied and the effects of kinds of ionic liquids, reaction temperature, reaction time, dosages of solvent, catalyst and methanol on methanolysis results were examined. It was showed that [Bmim][Cl] ionic liquid was of better performance as a solvent. The obtained optimum reaction conditions were m（[Bmim][Cl]）:m（PET）=2:1,m（methanol） :m（PET） =4:1,catalyst dosage（based on reaction mixture）5%, reaction temperature 160℃, reaction time 3.0h. Under above conditions, the conversion of PET and the yield of dimethyl terephthalate were 100% and >88% respectively. The ionic liquids could be reused 8 times without obvious decrease in the conversion of PET and yield of dimethyl terephthalate.The 2-ethylhexanolsis of PET in ionic liquids was studied and the effects of reaction time, ratio of materials, amount of ionic liquids and catalyst dosage on reaction results were examined. The obtained optimum reaction conditions were reflux temperature, m（[Bmim][Cl]）:m（PET）=2:1, n（2-EH）:n（PET）=3:1, m（catalyst）: m（PET）=1:100, reaction time 3.5h. Under above conditions, the conversion of PET could reach up to100% and yield of dioctyl terephthalate was over 90%. The ionic liquids could be reused 8 times without obvious decrease in the conversion of PET and yield of product.To our knowledge, there is no report in literature about the chemical depolymerization of PET in presence of ionic liquid.更多还原