采用减压蒸馏法处理乙二醇降解PET聚酯所产生的废液,并将处理后的废液用于再降解PET聚酯,通过红外光谱(FT-IR)对回收废液降解聚酯所得产物的结构进行表征;用热重分析(TG)和差示扫描量热法(DSC)测定降解产物的熔点和热稳定性;并通过酸值羟值测定和质谱(MS)分析对降解产物的平均分子量进行表征。结果表明:回收废液降解聚酯所得产物的主要成分是对苯二甲酸二乙二醇酯(BHET),还含有少量的二聚体和对苯二甲酸聚乙二醇酯,平均分子量为267g/mol,产物产率为82.40%。 Decompression distillation ethylene glycol degradation of PET polyester waste generated, and the treated waste liquid for further degradation of PET polyester, by infrared spectroscopy (FT-IR) on the recovery of waste polyester obtained The structure and structure of the product were characterized. The melting point and thermal stability of the degradation products were determined by TG and DSC. The degradation products were characterized by acid value and mass spectrometry (MS) The average molecular weight was characterized. The results showed that the main component of the product obtained from the waste water recycling polyester was ethylene terephthalate (BHET), a small amount of dimer and polyethylene terephthalate with average molecular weight of 267g / mol, the product yield was 82.40%.