Recycling of chemicals from waste plastics is important for the reutilization of resources and the reduction of environmental pollution. The phase behaviors of poly (1,4-cyclohexylene dimethylene terephthalate) (PCT) in water at different temperature and time were observed in a fused silica capillary reactor (FSCR) with a microscope. The effects of the reaction temperature (260−340 °C), the reaction time (30−90 min), and the mass ratio of water/PCT (6:1−14:1) on the degradation of PCT were studied in an autoclave reactor on the basis of the results obtained from the FSCR. Under our research conditions, depolymerization of both 1,4-cyclohexanedimethanol and terephthalic acid (TPA) generated mainly phenol, and the maximum yield of phenol was obtained at 340 °C after its reaction with a water/PCT mass ratio of 10:1 for 90 min. Moreover, a reaction mechanism of PCT degradation in subcritical water was proposed. Our results suggest that PCT can be depolymerized rapidly and completely in subcritical water to produce phenol, and this method is conducive to the recycling of waste PCT.

从废塑料中回收化学品对于资源的再利用和减少环境污染至关重要。在带有显微镜的熔融石英毛细管反应器（FSCR）中，观察了聚（1,4-环己二甲基对苯二甲酸亚丙基酯）（PCT）在水中在不同温度和时间下的相行为。研究了反应温度（260-340°C），反应时间（30-90 min）和水/ PCT的质量比（6：1-1-14：1）对PCT降解的影响。高压釜反应器基于从FSCR获得的结果。在我们的研究条件下，1,4-环己烷二甲醇和对苯二甲酸（TPA）均发生解聚，主要生成苯酚，与水/ PCT质量比为10：1的苯酚反应后，在340°C时可获得最大产率的苯酚。 90分钟 此外，提出了亚临界水中PCT降解的反应机理。我们的结果表明，PCT可以在亚临界水中迅速完全解聚，生成苯酚，这种方法有利于废PCT的回收。