摘要
为满足深海光电复合缆在高压力、强腐蚀性海水环境中的运行要求,文中选择具有良好阻水性能且可耐受直流高压的高密度聚乙烯(HDPE)作为电缆绝缘材料。但结晶度较高的HDPE耐环境应力开裂性能较差,为此采用交联改性来加强片晶间的作用力来保证材料在保持阻水性能的同时能极大地提高材料的耐开裂特性。鉴于HDPE加工温度高(~140℃),与传统的过氧化物交联及硅烷交联工艺适配性差的问题,提出了基于光敏的紫外光引发交联技术,配合一种含有多不饱和双键的交联助剂制备了不同交联度的HDPE材料。从拉伸与热延伸试验得出,随着材料交联度的提高,片晶间的相互作用明显增强,有效提升了材料的耐环境应力开裂性能(>900 h),并保持了优异的阻水特性(<0.125%);基于第一性原理计算,并结合空间电荷分布、直流电阻率与直流击穿强度测试得到,交联助剂的极性基团——羰基在材料内引入了0.8 eV的空穴陷阱与1.9 eV的电子深陷阱,在材料内部有效抑制了空间电荷注入现象,并提高了材料的直流电阻率,保持了材料的直流击穿强度。
To meet the operational demands of deep-sea optoelectronic composite cables subjected to high pressure and corrosive seawater environments,high-density polyethylene(HDPE)is chosen as insulating material due to its excellent water-blocking properties and resistance to DC high-voltage.However,HDPE with high crystallinity exhibits poor resistance to environmental stress cracking.To address this issue,cross-linking modification was employed to enhance inter-lamellar cohesion,thereby ensuring the material retains its water-blocking properties while significantly improving its resistance to cracking.Considering the high processing temperature of HDPE(~140℃)and its poor compatibility with traditional peroxide and silane cross-linking processes,a method for preparing HDPE materials with varying degrees of cross-linking was proposed by photosensitive ultraviolet-initiated cross-linking technology in conjunction with a cross-linking additive containing polyunsaturated double bonds.Tensile and thermal elongation test reveal that as the degree of cross-linking increases,inter-lamellar interactions are substantially strengthened,leading to improved resistance to environmental stress cracking.The cross-linking additives effectively enhance the resistance to environmental stress cracking(>900 h)while maintaining excellent water resistance(<0.125%).Based on first principles calculations and supported by analyses of space charge distribution,DC resistivity,and DC breakdown strength test,it is found that the polar groups of the cross-linking additives,particularly carbonyl group,introduce hole traps of 0.8 eV and deep electron traps of 1.9 eV within the material.This effectively suppresses the phenomenon of space charge injection and enhances the material's DC resistivity while preserving its DC breakdown strength.
作者
陈珍珍
谢书鸿
闫志雨
邱兴宇
牛学超
王凯
赵新东
杨佳明
Zhenzhen Chen;Shuhong Xie;Zhiyu Yan;Xingyu Qiu;Xuechao Niu;KaiWangXindong Zhao;Jiaming Yang(Zhongtian Technology Submarine Cable Co.,Ltd,Nantong 226010,China;Key Lab of Engineering Dielectrics and Their Application,Ministry of Education,Harbin University of Science and Technology,Harbin 150080,China)
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2024年第8期138-146,共9页
Polymer Materials Science & Engineering
关键词
高密度聚乙烯
紫外光辐照交联
耐环境应力开裂
直流电性能
high density polyethylene
UV irradiation crosslinking
resistance to environmental stress cracking
direct-current performance
