摘要
为研究化学交联对聚乙烯水树枝老化特性的影响,选用低密度聚乙烯(LDPE)、过氧化物交联聚乙烯、硅烷交联聚乙烯作为试验材料。采用水针电极法培养水树枝,用金相显微镜观测水树枝的形态,并统计了水树枝的尺寸和引发率;同时观测了试样的结晶形态,测定了试样的结晶度、交联度和杂质质量分数,并对比分析了交联前后及不同交联方式试样的电气性能。试验研究发现,交联对水树枝老化特性有显著的影响,产生这种影响的主要原因是交联使得聚乙烯的结晶形态发生变化。当试样的晶块尺寸大、数量少时,水树枝的平均生长速度较快;晶块尺寸小、数量多时,水树枝的平均生长速度较慢。交联的三维网状结构和副产物对交联聚乙烯的介电性能也会产生显著影响。
The relationship between chemical cross-linking and water treeing was studied. Low density polythene, peroxide cross-linked polyethylene and silane cross-linked polyethylene were chosen as the testing materials. During the experiments, liquid needle electrodes method was used for water tree development, and metallographic microscope was used for observation of water tree morphology and crystalline morphology of samples. Meanwhile, sizes and initiation rates of water trees were counted. Crystalline, cross-linking degree, impurity content and electrical performances of samples were measured. The experimental results reveal that, firstly, chemical cross linking can change the crystalline and crystal morphology of polythene, which makes the crystal blocks of polythene cross-linked small and compact; secondly, chemical cross-linking has a significant impact on water treeing. Before and after being cross-linked, difference of crystal block sizes is the main reason of difference of water treeing. The growth of water trees is faster in polythene samples in which crystal blocks are larger and the number of the crystal blocks is smaller. In contrast, water trees grow more slowly in other polythene samples in which crystal blocks are smaller in size and greater in number; finally, three-dimensional network structure and by-products of the cross-linked polythene have a significant impact on electrical properties of materials.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2011年第10期2477-2484,共8页
High Voltage Engineering
关键词
水树枝
化学交联
聚乙烯(PE)
交联聚乙烯(XLPE)
结晶形态
电气性能
water tree
chemical cross-linking
polyethylene （PE）
cross-linked polyethylene （XLPE）
crystalline morphology
electrical performances
