GIL中聚酯薄膜在电热作用下裂解机理的分子动力学模拟

doi:10.19595/j.cnki.1000-6753.tces.180889

Abstract
Figure/Table
References
Related Citation (7)

Download: PDF (58033 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract Polyethylene terephthalate (PET) is used as an electrode coating in gas insulation lines (GIL) to reduce the threat of metal particles to GIL operation. PET will gradually age under the influence of electricity, heat and other factors, eventually leading to insulation failure. In this paper, the micro-dynamic reaction path and the main product formation process of PET at high temperature were analyzed via ReaxFF, and the microscopic mechanism of PET insulation failure at high temperature and high field strength were obtained. A large number of highly reactive ester groups in PET are prone to fracture under the action of electricity and heat, which in turn leads to a decrease in the degree of polymerization of PET and the resistance to field strength. In the thermal cracking, it produces a large number of terephthalate, C₂H₄ and other small molecules, in which the former is easily combined with hydrogen ions to form PTA. At higher reaction temperatures, terephthalate decarboxylation is enhanced and the rate of CO₂ production is significantly accelerated. The main gas products such as C₂H₄, CO₂ and CO are accumulated in the interior of PET to form micropores. The local discharge will easily occur in the micropores and eventually lead to the breakdown of PET due to insulation failure. The electro-cracking reaction of PET chains with different degrees of polymerization was simulated. The results show that, the molecules are polarized and the internal force is weakened under the action of the electric field force. The morphology is also destroyed, and the thermal stability and mechanical strength are decreased.

Key words： Dielectrically coated electrodes polyester film pyrolysis microscopic mechanism reactive molecular dynamics

Received: 28 May 2018 Published: 27 November 2018

PACS:

TM215.1

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	Xin Zhe
	Zhao Tong
	Han Zhiyun
	Zou Liang
	Zhang Li

Cite this article:

Xin Zhe,Zhao Tong,Han Zhiyun等. Molecular Dynamics Simulation of the Pyrolysis Mechanism of Polyester Films in Gas Insulation Lines Under Electrothermal Stresses[J]. Transactions of China Electrotechnical Society, 2018, 33(22): 5196-5205.

URL:

https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.180889 OR https://dgjsxb.ces-transaction.com/EN/Y2018/V33/I22/5196

[1] 李庆民, 王健, 李伯涛, 等. GIS/GIL中金属微粒污染问题研究进展[J]. 高电压技术, 2016, 42(3): 849-860.
Li Qingmin, Wang Jian, Li Botao, et al.Review on metal particle contamination in GIS/GIL[J]. High Voltage Engineering, 2016, 42(3): 849-860.
[2] 美国公司发布新型高阻隔金属化聚酯薄膜[J]. 塑料科技, 2018, 46(3): 35.
[3] 王德诚. 东丽开发新型PET薄膜——高功能有机无机混合涂层薄膜——抑制加工过程的擦伤、异物析出、粗大突起[J]. 聚酯工业, 2017, 30(5): 19.
[4] 屠幼萍, 孙伟忠, 岳彩鹏, 等. 固体绝缘材料热老化电气特性的研究[J]. 电工技术学报, 2013, 28(1): 7-13.
Tu Youping, Sun Weizhong, Yue Caipeng, et al.Research on thermal aging electrical properties of polymer materials[J]. Transactions of China Electrotechnical Society, 2013, 28(1): 7-13.
[5] 陈广辉, 岳彩鹏, 王伟. 聚合物固体绝缘材料应用研究[J]. 电力科学与工程, 2011, 27(9): 8-11.
Chen Guanghui, Yue Caipeng, Wang Wei.Research on polymer solids insulating material[J]. Electric Power Science and Engineering, 2011, 27(9): 8-11.
[6] 王健, 李庆民, 李伯涛, 等. 直流应力下电极表面覆膜对金属微粒启举的影响机理研究[J]. 电工技术学报, 2015, 30(5): 119-127.
Wang Jian, Li Qingmin, Li Botao, et al.Mechanism analysis of the electrode-coating's impact on the particle-lifting under DC voltage[J]. Transactions of China Electrotechnical Society, 2015, 30(5): 119-127.
[7] 律方成, 刘宏宇, 李志兵, 等. 直流电压下SF₆气体中电极覆膜对金属微粒启举的影响机理[J]. 电工技术学报, 2017, 32(13): 239-247.
Lü Fangcheng, Liu Hongyu, Li Zhibing, et al.Influence mechanism of dielectric coated electrodes on metallic particle lift-off in SF₆ gas under DC voltage[J]. Transactions of China Electrotechnical Society, 2017, 32(13): 239-247.
[8] Boubakri A, Guermazi N, Elleuch K, et al.Study of UV-aging of thermoplastic polyurethane material[J]. Materials Science & Engineering A, 2010, 527(7-8): 1649-1654.
[9] 陆云才. 基于分子模拟的油纸绝缘老化机理及气体扩散行为研究[D]. 重庆: 重庆大学, 2007.
[10] 杨凯. 聚合物绝缘材料油中热老化特性研究[D]. 北京: 华北电力大学, 2014.
[11] 王伟, 杨凯, 刘晗, 等. PC和PET油中热老化分解物特性分析[J]. 电工技术学报, 2016, 31(5): 152-163.
Wang Wei, Yang Kai, Liu Han, et al.Analysis of the thermal aging decomposition characteristics of PC and PET in oil[J]. Transactions of China Electro- technical Society, 2016, 31(5): 152-163.
[12] 杨凯, 王伟, 杜家振, 等. PC和PET油中电热老化过程中聚合度和介损特性分析[J]. 电工技术学报, 2014, 29(4): 282-289.
Yang Kai, Wang Wei, Du Jiazhen, et al.Analysis on DP and tanδ characteristics of PC and PET in the electrical-thermal aging process in oil[J]. Transa- ctions of China Electrotechnical Society, 2014, 29(4): 282-289.
[13] 高宁, 王一超, 刘育红. 丙炔基双酚A醚硼聚合物热解过程的ReaxFF分子动力学模拟[J]. 化工学报, 2015, 66(4): 1557-1564.
Gao Ning, Wang Yichao, Liu Yuhong.Molecular dynamics simulations of thermal pyrolysis of novel dipropargyl ether of bisphenol A based boron- containing polymer[J]. CIESC Journal, 2015, 66(4): 1557-1564.
[14] 李庆民, 黄旭炜, 刘涛, 等. 分子模拟技术在高电压绝缘领域的应用进展[J]. 电工技术学报, 2016, 31(12): 1-13.
Li Qingmin, Huang Xuwei, Liu Tao, et al.Application progresses of molecular simulation methodology in the area of high voltage insulation[J]. Transactions of China Electrotechnical Society, 2016, 31(12): 1-13.
[15] Zhang Zhiqiang, Yan Kefeng, Zhang Jilong.ReaxFF molecular dynamics simulations of the initial pyrolysis mechanism of unsaturated triglyceride[J]. Journal of Molecular Modeling, 2014, 20(3): 2127.
[16] Chenoweth K, Duin A C T V, Goddard W A. ReaxFF reactive force field for molecular dynamics simulations of hydrocarbon oxidation[J]. Journal of Physical Chemistry A, 2008, 112(5): 1040-1053.
[17] 鲁旭, 韩帅, 李庆民, 等. 聚酰亚胺高温裂解机理的反应分子动力学模拟[J]. 电工技术学报, 2016, 31(12): 14-23.
Lu Xu, Han Shuai, Li Qingmin, et al.Reactive molecular dynamics simulation of polyimide pyrolysis mechanism at high temperature[J]. Transactions of China Electrotechnical Society, 2016, 31(12): 14-23.
[18] Duin A C T V, Dasgupta S, Lorant F, et al. ReaxFF: a reactive force field for hydrocarbons[J]. Journal of Physical Chemistry A, 2001, 105(41): 9396-9409.
[19] 赵彤, 石雷, 张远涛, 等. 基于分子模拟的绝缘纸高温裂解过程水分产生及其破坏作用研究[J]. 中国电机工程学报, 2017, 37(15): 4548-4556.
Zhao Tong, Shi Lei, Zhang Yuantao, et al.Study on H₂O formation during the pyrolysis of insulating paper and its destructive effect based on molecular simulation[J]. Proceedings of the CSEE, 2017, 37(15): 4548-4556.
[20] 廖瑞金, 胡舰, 杨丽君, 等. 变压器绝缘纸热老化降解微观机理的分子模拟研究[J]. 高电压技术, 2009, 35(7): 1565-1570.
Liao Ruijin, Hu Jian, Yang Lijun, et al.Molecular simulation for thermal degradative micromechanism of power transformer insulation paper[J]. High Voltage Engineering, 2009, 35(7): 1565-1570.
[21] 罗杨, 吴广宁, 曹开江, 等. 聚酰亚胺分子降解的微观动力学模拟[J]. 高电压技术, 2012, 38(10): 2707-2713.
Luo Yang, Wu Guangning, Cao Kaijiang, et al.Dynamic simulation for pyrolysis micro-mechanism of polyimide[J]. High Voltage Engineering, 2012, 38(10): 2707-2713.
[22] 张黎明, 刘创华, 方琼, 等. 热老化对管型母线绝缘材料PET薄膜性能的影响研究[J]. 绝缘材料, 2016, 49(8): 44-48.
Zhang Liming, Liu Chuanghua, Fang Qiong, et al.Effect of thermal ageing on properties of PET films as novel insulating material for tubular bus[J]. Insulating Materials, 2016, 49(8): 44-48.
[23] Neyts E C, Brault P.Molecular dynamics simulations for plasma-surface interactions[J]. Plasma Processes & Polymers, 2017, 14(1-2).
[24] 蔡文生. Christophe Chipot.高性能大规模分子动力学的前沿进展——近35年生物体系的分子动力学模拟研究回顾[J]. 化学学报, 2013, 71(2): 24-33.
Cai Wensheng. Christophe Chipot.Frontiers in high-performance, large-scale molecular dynamics 35 years of molecular-dynamics simulations of biolo- gical systems[J]. Acta Chimica Sinica, 2013, 71(2): 24-33.
[25] 解兵, 梁帅伟, 杨丽君, 等. 油纸绝缘电-热老化寿命模型的选择研究[J]. 高电压技术, 2006, 32(3): 21-23.
Xie Bing, Liang Shuaiwei, Yang Lijun, et al.Analysis and choice of electro-thermal aging life models used in oil-paper insulation[J]. High Voltage Engineering, 2006, 32(3): 21-23.
[26] 梁超, 李文刚, 张幼维, 等. PET纤维热老化的研究[J]. 合成技术及应用, 2014(1): 15-18.
Liang Chao, Li Wengang, Zhang Youwei, et al.Study on thermal alageing of PET fiber[J]. Synthetic Technology & Application, 2014(1): 15-18.
[27] 易志文, 闫婷伟, 周贵强, 等. 聚酯纤维微观形态结构与老化特性的关系[J]. 合成纤维, 2015, 44(1): 12-18.
Yi Zhiwen, Yan Tingwei, Zhou Guiqiang, et al.Relationship between microstructure and aging properties of polyester fibers[J]. Synthetic Fiber in China, 2015, 44(1): 12-18.
[28] 黄振侬, 梁疆莉, 阮小林, 等. 高效液相色谱法测定工作场所空气中对苯二甲酸[J]. 中国职业医学, 2006, 33(4): 295-296.
Huang Zhennong, Liang Jiangli, Ruan Xiaolin, et al.Study on determination of terephthalic acid with high performancd liquid chromatography (HPLC) in atmosphere of workplaces[J]. China Occupational Medicine, 2006, 33(4): 295-296.
[29] Heywood R J, Stevens G C, Ferguson C, et al.Life assessment of cable paper using slow thermal ramp methods[J]. Thermochimica Acta, 1999, 332(2): 189-195.
[30] 肖迎红, Anne Bergeret, Marie-Pierre Foulcmp.PET的湿热老化性能研究[J]. 塑料科技, 2001(4): 22-24.
Xiao Yinghong, Anne Bergeret, Marie-Pierre Foulcmp. study of the hygrothermal ageing behavior of PET[J]. Plastics Science & Technology, 2001(4): 22-24.
[31] 杜斌, 杨睿, 谢续明. 聚对苯二甲酸乙二醇酯水热老化过程中的物理和化学变化[J]. 塑料, 2011, 40(5): 24-27.
Du Bin, Yang Rui, Xie Xuming.Physical and chemical changes during hydrothermal ageing of poly (ethylene terephthalate)[J]. Plastics, 2011, 40(5): 24-27.
[32] Can N, Aras F, Alekperov V A, et al.Investigation on aging mechanism of polyester under combined stresses[J]. IEEE Electrical Insulation Magazine, 2016, 32(4): 38-42.
[33] 李富平, 王伟, 刘凯, 等. 聚碳酸酯薄膜和聚酯薄膜在变压器油中电热老化的耐电性能对比分析[J]. 绝缘材料, 2015, 48(1): 20-24, 29.
Li Fuping, Wang Wei, Liu Kai, et al.Conparative analysis of withstand voltage characteristics of PC and PET film after electrical-thermal ageing in transformer oil[J]. Insulating Materials, 2015, 48(1): 20-24, 29.
[34] 廖瑞金, 何利华, 吕彦冬, 等. 纳米Al₂O₃掺杂对油纸绝缘热老化特性的影响[J]. 电工技术学报, 2017, 32(15): 207-215.
Liao Ruijin, He Lihua, Lü Yandong, et al.Influence of nano-Al₂O₃ on properties of oil-paper insulation during thermal aging process[J]. Transactions of China Electrotechnical Society, 2017, 32(15): 207-215.