Initial Research On The Interaction Between PET And Cotton-polyester Blended Fibers And Ionic Liquid

In this study, the ionic liquids were introduced as reaction medium and catalysts.The initial research on the interaction between PET or cotton-polyester blended fibersand ionic liquid was carried out.(1) Three neutral ionic liquid ([EOmim]Cl,[Bmim]Cl,[Amim]Cl) weresynthesized directly, and three corresponding basic ionic liquid ([EOmim]OH,[Bmim]OH,[Amim]OH) were obtained after ion exchange.(2) Firstly, ionic liquids were as reaction medium on dissolution of PET. Duringthe PET dissolution, the effect of reaction time and temperature on the solubility wasstudied. It was showed that both the neutral ionic liquid and basic ionic liquid had acertain PET dissolution, while the neutral ionic liquid was better. The lysate structurewas characterized by XRD and GPC. The dissolution kinetics of PET in ionic liquidwas also investigated. The repeatable property of ionic liquid was studied. It wassuggested that there were no obvious decrease of PET solubility and lysate yield afterfive times. On the contrary, the yield was increased with the use number of ionicliquid.(3) Secondly, ionic liquids were as catalysts on the alcoholysis of PET. Duringthe catalytic alcoholysis of PET, the orthogonal experiments were employed toanalyze the effect of reaction time, temperature, catalyst dosage and m (PET): m(EG)on the degradation. It was showed that the PET didn’t alcoholysis by neutral ionicliquid with quite low degradation ratio of PET. However, the basic ionic liquidshowed better catalysis. In the meantime, the structure of degradation products wascharacterized. Finally, from the view of low carbon, environment protection and greeneconomy, explore the optimum degradation process of abandoned PET.(4) Thirdly, ionic liquids were as catalysts in separation of the mixedcotton-polyester blended fibers. During the degradation of cotton-polyester blendedfibers, the basic ionic liquids were adopted as catalysts for alcoholysis of PET. It wasshowed that PET was completely degradated, the cotton fibers can keep their originalshape under the catalysis of basic ionic liquid, which achieved the separation ofcotton-polyester blended fibers.