Catalyzed Depolymerization Of Polycarbonate In Supercritical/Subcritical Ethanol

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...