微量氧化石墨烯改性聚酯的制备及性能研究

吴跃亚 蒲新明 郑兵 张顺花

摘 要：为探究微量氧化石墨烯在PET合成过程中的作用以及对GO/PET改性聚酯结构的影响，以PTA、EG为单体，微量GO为改性剂，采用原位聚合直接酯化法合成GO/PET改性聚酯。通过特性黏度、端羧基含量、DSC、TG以及红外光谱分析，结果表明：微量GO的加入提高了PET的特性黏度和黏均分子量，特性黏度范围在0.68～0.73dL/g;GO/PET的端羧基（—COOH）含量均小于纯PET的端羧基含量，说明GO的加入有利于PET的合成，能够使聚酯的合成更加完善;FTIR分析得到，GO经共聚反应后，1720 cm-1处的C=O峰与719 cm-1处的C—H峰都明显增强，推测PET大分子链已通过化学键结合的方式成功引入到GO片上;DSC、TG分析得到，微量GO的加入加快了试样的结晶速率以及增强了试样的热稳定性。

关键词：氧化石墨烯;微量;PET;改性;原位聚合;结构性能

中图分类号： TB34

文献标志码：A

文章编号：1009-265X（2021）04-0096-06

Abstract： In order to explore the role of trace amount of graphene oxide in the process of PET synthesis and its influence on the structure of GO/PET modified polyester， PTA and EG were used as monomers， and trace amount of GO was used as a modifier to synthesize GO/PET modified polyester by the in-situ polymerization and direct esterification method. The analysis results of intrinsic viscosity， terminal carboxyl group content， DSC， TG and infrared spectroscopy showed that the addition of trace amount of GO increased the intrinsic viscosity and viscosity average molecular weight of PET， and the intrinsic viscosity ranged from 0.68 to 0.73 dL/g. The terminal carboxyl group （-COOH） content of GO/PET was lower than that of pure PET， indicating that the addition of GO is beneficial to the synthesis of PET and can make the synthesis of polyester more perfect. FTIR analysis showed that after GO copolymerization， The C=O peak at 1720 cm-1 and the CH peak at 719 cm-1 were both significantly enhanced. It is speculated that the PET macromolecular chain has been successfully introduced into the GO sheet through chemical bonding. DSC and TG analysis showed that the addition of trace amount of GO accelerated the crystallization rate of the samples and enhanced the thermal stability of the samples.

Key words： graphene oxide; trace amount; PET; modification; in-situ polymerization; structural properties

聚对苯二甲酸乙二醇酯（PET）是一种应用十分广泛的热塑性树脂，具有熔点高、成型性好、生产成本低和机械性能优良等优点，其在电子器件、合成纤维和工程塑料等方面有广泛的应用，在全球范围内有着巨大的需求量[1-3]。工业用聚酯纤维对纤维的物理机械性能要求极高，如高强度、低热收缩率等，这对原料的品质和加工性能有更高的要求，此时添加改性剂是最常见的方法[4]。石墨烯材料具有杨氏模量高（约为1 100 GPa）、导电（室温载流子迁移率为2105 cm2/Vs）和导热（约为5 000 J/mKs）等[6-10]特性。用石墨烯改性高分子材料应用广泛[5]，近年来本课题组研究发现，石墨烯的加入对PET聚酯的玻璃化转变温度、结晶速率、结晶温度以及热稳定性都有显著的提高[11-12]。……