二氧化碳辅助甲醇无催化降解聚乳酸  

CO_(2)-Assisted Methanol Non-Catalytic Degradation of PLA

作　　者：沈仲卿 贾子先 张杰 银建中[1] SHEN Zhongqing;JIA Zixian;ZHANG Jie;YIN Jianzhong(Dalian University of Technology,Dalian,Liaoning 116024;SINOPEC(Dalian)Research Institute of Petroleum and Petrochemicals Co.,Ltd.,Dalian,Liaoning 116045)

机构地区：[1]大连理工大学化工学院,辽宁大连116024 [2]中国石油化工股份有限公司大连石油化工研究院,辽宁大连116045

出　　处：《化工装备技术》2025年第1期1-5,共5页Chemical Equipment Technology

摘　　要：全球废塑料问题日益严重。聚乳酸是一种生物可降解材料,虽然具有潜在的环保优势,但较高的生产成本和对特定降解环境的依赖,制约了其规模化应用。通过化学回收方法,聚乳酸可以被转化为单体或高价值化学品,实现闭环使用。重点探讨了甲醇醇解法,引入二氧化碳作为辅助手段,实现了聚乳酸的无催化降解。通过在不同的二氧化碳初始压力下进行反应,控制反应温度、反应时间和搅拌速率,研究了二氧化碳对甲醇降解聚乳酸和乳酸甲酯收率的影响。结果表明,二氧化碳的加入显著提高了聚乳酸的降解率和乳酸甲酯的收率。在最佳降解条件下,即二氧化碳的压力为0.5 MPa,反应温度为175℃,反应时间为120 min,聚乳酸的降解率达到100%,乳酸甲酯的收率为78.18%。此外,还对二氧化碳辅助甲醇降解聚乳酸过程进行了动力学分析。结果表明,在175℃条件下,0.5 MPa二氧化碳显著提高了反应速率,反应活化能为27.17 kJ/mol。The global problem of plastic waste is becoming increasingly severe.Polylactic acid(PLA)is a biodegradable material that has potential environmental advantages,but its high production cost and dependence on specific degradation environments limit its large-scale application.Through chemical recycling methods,PLA can be converted into monomers or high-value chemicals,achieving closed-loop use.The focus was on the methanol alcoholysis method,and carbon dioxide was introduced as an auxiliary means to achieve the non-catalytic degradation of PLA.The effect of carbon dioxide on the yield of methanol degradation of PLA and methyl lactate was studied by controlling the reaction temperature,reaction time,and stirring speed under different initial pressures of carbon dioxide.The results showed that the addition of carbon dioxide significantly improved the degradation rate of PLA and the yield of methyl lactate.Under the optimal conditions of initial carbon dioxide pressure of 0.5 MPa,reaction temperature of 175℃,and reaction time of 120 minutes,the degradation rate of polylactic acid reached 100%,and the yield of methyl lactate was 78.18%.In addition,a kinetic analysis was conducted on the process of carbon dioxide assisted methanol degradation of PLA.The results showed that at 175℃,0.5 MPa carbon dioxide significantly increased the reaction rate,and the activation energy of the reaction was 27.17 kJ/mol.

关 键 词：聚乳酸 二氧化碳辅助 甲醇降解 乳酸甲酯 

分 类 号：O622[理学—有机化学]