The characteristics of supercritical fluids and its application in chemical recycling of polymer were introduced in the paper. Recent studies on recycling of polycarbonate (PC) by pryolysis, methanolysis or depolymerization m supercritical fluids are summarized.The experiment was carried out in a batch autoclave with magnetically driving agitator. The depolymerization products were analyzed by Gas Chromatography and Mass Spectrometry (GC-MS), Gas Chromatography (GC), Fourier-transform Infrared Spectroscopy (FT-IR), respectively.The thermal stability of Bisphenol A(BPA) in subcritical/supercritical ethanol and methanol with or without catalyst was carried out on the condition of temperature 150-270℃, pressure 1.2~9.4MPa, reaction time 15min, ratio of ethanol/BPA 8.0, respectively. The thermal stability of BPA in subcritical and supercritical fluid was decreased as temperature increased with or without catalyst. BPA is more stable in subcritical/supercritical ethanol than that in subcritical/supercritical methanol at the same temperature without catalyst. This result offered basis of selecting depolymerization fluid and operating parameter correctly.Depolymerization of PC in subcritical/supercritical ethanol was carried out on the condition of temperature 160-260 ℃ , pressure 1.4~8.5MPa, reaction time 15~60min, ratio of ethanol/PC 3.0-10.0, respectively. Depolymerization yield increases with the temperature and...
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