PPET 共聚酯的结构表征及其结晶和热性能研究  

Study on Structural Characterization and Crystallization Property,Thermal Performance of PPET Copolyesters

作　　者：马城华 陈延明[2] 吴佩华 林妍妍 王立岩[2] 

机构地区：[1]中国石油辽阳石化分公司,辽宁辽阳111003 [2]沈阳工业大学石油化工学院,辽宁辽阳111003

出　　处：《中国塑料》2017年第4期30-34,共5页China Plastics

摘　　要：采用直接酯化熔融缩聚法合成了一系列不同含量的1,2-丙二醇(1,2-PG)改性共聚酯(PPET),并用凝胶渗透色谱、核磁共振光谱对其结构进行了较为系统的表征,用差示扫描量热分析和热失重分析对其结晶性能和热性能进行了研究。结果表明,PPET的数均相对分子质量均在29000以上,相对分子质量分布系数在1.9~2.1之间;1,2-PG留在大分子链上的比例相对投料比减少,说明1,2-PG与乙二醇(EG)相比不容易接入到分子链上;同PET相比,PPET共聚酯的结晶能力降低,熔点降低,当1,2-PG的加入量为20%(质量分数,下同)时,PPET熔点较PET熔点降低了约24℃;PPET共聚酯具有与普通聚酯相近的热稳定性。A series of co-polyesters [poly（propylene-co-ethylene terephthalate）,PPET]were synthesized by adding various contents of 1,2-propylene glycol（PG）through a direct esterification method.Their structures were characterized systematically and their crystallization property and thermal performance were investigated.Gel permeation chromatography analysis indicated that the PPET has a number average molecular weight of over 29000 and a molecular weight distribution of 1.9-2.1.Nuclear magnetic resonance（NMR）spectroscopic characterization suggested that the weight fraction of PG remained in macromolecular chains was lower than its feed ratio,indicating that PG was more difficult to be introduced into the macromolecular chain than EG.Differential scanning calorimetry analysis demonstrated that the crystallization capability of PPET was reduced in comparison with poly（ethylene terephthalate）（PET）,and their melting point also decreased by24 ℃ when 20wt% PG was incorporated.In addition,PPET exhibited a thermal stability similar to the conventional PET polyester according to thermogravimetric analysis.

关 键 词：1 2-丙二醇 改性共聚酯 结构 结晶 热性能 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]