摘要
随着聚对苯二甲酸乙二醇酯(PET)用量的不断增大,对PET的回收利用的研究日益受到关注.PET化学解聚方法包括水解、甲醇解聚和乙二醇解聚等[1-6].微波在化学领域中的应用日益广泛[7,8],在微波作用下,PET在中性水中可以完全解聚为对苯二甲酸和乙二醇,不需加催化剂,反应条件温和,快速且转化率高[9].在PET的解聚反应研究中.
Polyethylene terephthalate(PET)resin was hydrolyzed to terephthalate acid(TPA)and ethylene glycol(EG)under microwave irradiation.The effects of crystallinity on the depolymerization of PET was investigated.PET resin was isothermal crystallized at temperature of 140,170,200 and 230℃for 5 hours,the crystallinity of the resin was 25.7%,29.5%,33.9%and 40.6%,respectively,then the resin with different crystallinity was hydrolyzed under microwave irriadition.Under the same conditions of hydrolytic depolymerization,the degree of PET depolymerization decreased from 72.8%to 69.34%with the increase of crystallinity of PET resin,the rate of depolymerization varied little with the increasing of crystallinity of PET,this indicated that the crystallinity of PET has little effect on the hydrolytic depolymerization.The crystallinity of PET was increased during the temperature elevating process of the hydrolytic depolymerization.Investigation by DSC proved that the crystallinity of PET resin increased notability during the same temperature elevating process as the hydrolyzed depolymerization.According to the theory that depolymerization was firstly proceed in the amorphous phase,the crystallinity should increase during the reaction.However,the crystallinity of PET residue was decreased during all the reaction process,this indicates that the hydrolysis did not preferentially occur in the amorphous phase.
作者
刘立新
刘若旺
张东
安立佳
王禹
LIU Li-Xin;LIU Ruo-Wang;ZHANG Dong;AN Li-Jia;WANG Yu(Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;Institute of Applied Chemistry,Wenzhou University,Wenzhou 325027,China;School of Chemistry&Chemical Engineering,Daqing Petroleum Institute,Daqing 163318,China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第12期2394-2396,共3页
Chemical Journal of Chinese Universities
基金
国家自然科学基金专项基金(批准号:20474043)资助
