电缆绝缘用聚丙烯/弹性体复合材料的高温介电性能研究

doi:10.19595/j.cnki.1000-6753.tces.221887

Abstract
Figure/Table
References (0)
Related Citation (13)

Download: PDF (1526 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract

Polypropylene (PP), which has excellent electrical properties, is a research hotspot of potential recyclable cable insulation materials at present. Nevertheless, PP is not capable as cable insulation material because of its stiffness and brittleness. Further modification should be studied for cable insulation applications. Elastomers are often used to improve the mechanical properties of PP. Because of the large difference in melting point between PP and elastomer, the enhanced relaxation of segments at high temperatures results in a significant deterioration of electrical properties. Therefore, β-nucleating agent was used to regulate the crystal morphology of PP in order to optimize the high temperature dielectric properties of polypropylene and elastomer blends.
Firstly, blends were prepared with and without nucleating agent in micro twin-screw extruder, for polyolefin elastomer (POE) contents of 20, 40 and 60% in weight. In the case of blends nucleated with TMB-5, the PP was previously melt blended with the additive at 0.06 wt% and subsequently blended with the elastomer. The changes in microstructure of specimens were tested through wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The morphologies of the crystals were observed by scanning electron microscopy (SEM). The structure and molecular motion information of the specimen were reflected by the dynamic mechanical thermal analysis. The mechanical and electrical properties were all investigated, with emphasis on the dielectric properties at different temperatures.
The results show that, for samples incorporating β-nucleating agent, β-crystals appear and ethylene crystals disappear. The introduction of β-crystals significantly improves the tensile strength while retaining the toughening effect of POE. The tensile strength of POE40-β is 46.1% higher than POE40. Compared with the POE system, the high-temperature mechanical stability of the POE/nucleating agent system is improved, and the high-temperature AC breakdown strength also increases significantly. At 90℃, the AC breakdown strength of POE40-β is 11.4% higher than POE40. More importantly, the dielectric constant and the loss of the POE system significantly increase at high temperatures and low frequency. The more elastomer content, the more obvious the rise. For the POE/nucleating agent system, the addition of β-nucleating agent inhibits the occurrence of this phenomenon. The dielectric constant does not rise at high temperatures and low frequency, and the loss decreases by an order of magnitude from 10^-2 to 10^-3 at 90℃ and power frequency.
The following conclusions can be drawn from the experimental results: (1) The introduction of β-crystals enhances the flexibility and high-temperature mechanical stability of polypropylene and elastomer blends. (2) The specimen incorporating β-nucleating agent has higher AC breakdown strength. (3) The addition of β-nucleating agent inhibits the compatibility between polypropylene and elastomer and weakens the effect of interface polarization, which makes it show more excellent dielectric properties.

Key words： Polypropylene elastomer toughening polymorphism regulation dielectric properties

Received: 07 October 2022

PACS:

TM215

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	Jiang Yikai
	Xu Man
	Wang Ruofei
	Xu Jing
	Lu Wenxian

Cite this article:

Jiang Yikai,Xu Man,Wang Ruofei等. Study on High Temperature Dielectric Properties of Polypropylene and Elastomer Blends for Cable Insulation[J]. Transactions of China Electrotechnical Society, 0, (): 221887-221887.

URL:

https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.221887 OR https://dgjsxb.ces-transaction.com/EN/Y0/V/I/221887

[1] 杜伯学, 韩晨磊, 李进, 等. 高压直流电缆聚乙烯绝缘材料研究现状[J]. 电工技术学报, 2019, 34(1): 179-191.
Du Boxue, Han Chenlei, Li Jin, et al.Research status of polyethylene insulation for high voltage direct current cables[J]. Transactions of China Electrotechnical Society, 2019, 34(1): 179-191.
[2] 石逸雯, 陈向荣, 孟繁博, 等. 电压稳定剂及其含量对高压直流用500kV XLPE电缆材料绝缘性能的影响[J]. 电工技术学报, 2022, 37(22): 5851-5861.
Shi Yiwen, Chen Xiangrong, Meng Fanbo, et al.The effect of voltage stabilizer and its content on the insulation properties of 500kV HVDC cable insulation materials[J]. Transactions of China Electrotechnical Society, 2022, 37(22): 5851-5861.
[3] 雷伟群, 刘冠芳, 耿涛, 等. XLPE/SiO₂纳米复合材料长期直流老化特征寿命恶化分析[J]. 电工技术学报, 2022, 37(2): 311-321.
Lei Weiqun, Liu Guanfang, Geng Tao, et al.Analysis on the characteristic lifetime deterioration of XLPE/SiO₂ nano-composites after long-term DC aging[J]. Transactions of China Electrotechnical Society, 2022, 37(2): 311-321.
[4] 洪泽林, 戴超, 张梦甜, 等. 热老化对电压稳定剂改善交联聚乙烯绝缘性能的影响[J]. 电工技术学报, 2021, 36(增刊1): 8-13.
Hong Zelin, Dai Chao, Zhang Mengtian, et al.Effect of thermal aging on voltage stabilizer to enhance insulation properties of cross-linked polyethylene[J]. Transactions of China Electrotechnical Society, 2021, 36(S1): 8-13.
[5] 彭兆伟, 关永刚, 张灵, 等. β成核剂含量对等规聚丙烯电导电流和空间电荷特性的影响[J]. 电工技术学报, 2019, 34(7): 1527-1535.
Peng Zhaowei, Guan Yonggang, Zhang Ling, et al.Influence of β-nucleating agent content on conduction current and space charge characteristics in isotactic polypropylene[J]. Transactions of China Electrotechnical Society, 2019, 34(7): 1527-1535.
[6] Huang Xingyi, Zhang Jun, Jiang Pingkai, et al.Material progress toward recyclable insulation of power cables part 2: Polypropylene-based thermoplastic materials[J]. IEEE Electrical Insulation Magazine, 2020, 36(1): 8-18.
[7] Wald D, Igbinovia F O, Raikisto P.Thermoplastic insulation system for power cables[C]//2020 IEEE PES/IAS PowerAfrica, Nairobi, Kenya, 2020: 1-5.
[8] Hosier I L, Vaughan A S, Swingler S G.An investigation of the potential of polypropylene and its blends for use in recyclable high voltage cable insulation systems[J]. Journal of Materials Science, 2011, 46(11): 4058-4070.
[9] Wu Yunhui, Zha Junwei, Li Weikang, et al.A remarkable suppression on space charge in isotatic polypropylene by inducing the β-crystal formation[J]. Applied Physics Letters, 2015, 107(11): 112901.
[10] Zhou Yao, Hu Jun, Dang Bin, et al.Effect of different nanoparticles on tuning electrical properties of polypropylene nanocomposites[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2017, 24(3): 1380-1389.
[11] Cao Weikang, Li Zhe, Sheng Gehao, et al.Insulating property of polypropylene nanocomposites filled with nano-MgO of different concentration[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2017, 24(3): 1430-1437.
[12] Zhou Yao, He Jinliang, Hu Jun, et al.Evaluation of polypropylene/polyolefin elastomer blends for potential recyclable HVDC cable insulation applications[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2015, 22(2): 673-681.
[13] 徐航, 杜伯学, 李进, 等. 聚丙烯/弹性体复合材料机械与空间电荷特性[J]. 高电压技术, 2019, 45(10): 3214-3220.
Xu Hang, Du Boxue, Li Jin, et al.Mechanical and space charge properties of polypropylene/elastomer blends[J]. High Voltage Engineering, 2019, 45(10): 3214-3220.
[14] 赵洪, 栗松, 郑昌佶, 等. 聚丙烯/聚烯烃弹性体复合材料物理机械性能及交流电性能[J]. 电机与控制学报, 2020, 24(3): 28-37.
Zhao Hong, Li Song, Zheng Changji, et al.AC performance and physical/mechanical properties of polypropylene/polyolefin elastomers blends[J]. Electric Machines and Control, 2020, 24(3): 28-37.
[15] 赵洪, 袁鑫, 杨佳明, 等. 弹性体/聚丙烯与塑性体/聚丙烯复合材料的力学及介电性能[J]. 高分子材料科学与工程, 2020, 36(10): 44-50.
Zhao Hong, Yuan Xin, Yang Jiaming, et al.Mechanical and dielectric properties of elastomer/polypropylene and plastomer/polypropylene composites[J]. Polymer Materials Science & Engineering, 2020, 36(10): 44-50.
[16] Zhang Wei, Xu Man, Huang Kaiwen, et al.Effect of β-crystals on the mechanical and electrica properties of β-nucleated isotactic polypropylene[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2019, 26(3): 714-721.
[17] 张伟, 徐曼, 陈光辉, 等. 等规和嵌段聚丙烯的结构和性能[J]. 高电压技术, 2017, 43(11): 3634-3644.
Zhang Wei, Xu Man, Chen G, et al.Structure and properties of isotactic polypropylene and ethylene-propylene copolymer[J]. High Voltage Engineering, 2017, 43(11): 3634-3644.
[18] Huang Kaiwen, Xu Man, Xue Zhigang, et al.Study on the structure and mechanical and electrical properties of β-crystal blended polypropylene[C]//22nd International Symposium on High Voltage Engineering, Xi'an, China, 2021: 1156-1161.
[19] Fanegas N, Gómez M A, Marco C, et al.Influence of a nucleating agent on the crystallization behaviour of isotactic polypropylene and elastomer blends[J]. Polymer, 2007, 48(18): 5324-5331.
[20] Busse K, Kressler J, Maier R D, et al.Tailoring of the α-, β-, and γ-modification in isotactic polypropene and propene/ethene random copolymers[J]. Macromolecules, 2000, 33(23): 8775-8780.
[21] Rybnikář F.Transition of β to α phase in isotactic polypropylene[J]. Journal of Macromolecular Science, Part B, 1991, 30(3): 201-223.
[22] 陈泽龙, 周凯, 李天华, 等. XLPE粘弹性与水树自恢复后微观形貌变化的关联[J]. 高电压技术, 2019, 45(11): 3579-3586.
Chen Zelong, Zhou Kai, Li Tianhua, et al.Correlationship between viscoelasticity of XLPE and water tree microstructure changes after self-recovery[J]. High Voltage Engineering, 2019, 45(11): 3579-3586.