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Ionic liquids as in the 21st century green solvents, under atmospheric pressure, a relatively low temperature, the polymer effectively degrade recyclable monomers. This article focuses on review polycarbonate recycled and take advantage of the current situation at home and abroad about the the depolymerization progress polymer in the ionic liquid system, the ionic liquid system is carried out on the basis of polycarbonate (PC) the depolymerization exploratory research. Select the five ionic liquid [Hmim the the CF 3 the SO 3 , [mim] HSO 4 , [BMSIM] the CF 3 SO 3 , [Hmim] HSO 4 , [Bzmim] CF 3 SO 3 as depolymerization reaction medium, the target product to bisphenol A (BPA) and diphenyl carbonate (DPC) for the depolymerization, through PC depolymerization effect contrast, filter out a better ionic liquid [Hmim] CF 3 SO 3 , to further explore the reaction conditions on the PC depolymerization rate, the yield of the main product. Experiments using Fourier transform infrared spectroscopy (FT-IR), gas chromatography (GC), gas chromatography - mass spectrum (GC-MS), high performance liquid chromatography (HPLC), liquid chromatography - mass spectroscopy (LC-MS) depolymerization product Qualitative and quantitative analysis. Ionic liquid dosage 4.0-20.0 g / gPC conditions at a temperature of 130-210 ° C, reaction time 3-24h, PC [Hmim] CF 3 SO 3 The depolymerization reaction was studied. The results show that: the depolymerization product BPA, higher selectivity; BPA yield of the main product with the reaction temperature, the reaction time and elevated, to obtain a higher yield, the reaction temperature is relatively low , it is necessary to extend the reaction time; can, simply a shorter reaction time when the reaction temperature is relatively high. When the reaction temperature of 170 ° C, the reaction time was 18h, ionic liquid dosage of 12.0 g / gPC BPA yield up to 84.4%. Chain features combined with the PC through of PC depolymerization product analysis, preliminary proposed PC [Hmim CF 3 SO 3 in the depolymerization mechanism. Ethylene glycol as a depolymerization reaction medium, Comparative study of the non-ionic liquid system PC depolymerization effect. Experimental results show that the reaction temperature was 170 ° C, the reaction time is 15H, the glycol used in an amount of 8.0 ml / GPC, Zn (Ac) catalyst 0.5% under the condition of 2 Dosage PC depolymerization rate 98.3 BPA yield of 63.7%, lower than the same reaction temperature [Hmim CF 3 SO 3 BPA in yield. Through the ionic liquid, and the effect of PC depolymerization Task Force supercritical fluid (water, methanol, ethanol) depolymerization effect contrast, found [Hmim] CF 3 SO 3 , ultra subcritical ethanol, methanol - water co-solvent in the PC can achieve effective degradation, and higher BPA yield of the main product, and higher than 80%, but the ionic liquid depolymerization PC depolymerization product separation difficulties, the use of ionic liquid circulation , ionic liquid depolymerization mechanism and \
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