电缆附件用环氧浇注料固化动力学及绝缘特性

Curing Kinetics and Insulation Characteristics in Casting Material of Epoxy Resin for Cable Accessories

通过对国内外典型环氧浇注材料固化反应动力学的分析,计算得到快速固化工艺参数,通过对固化物的Tg的测量,验证了参数制定的有效性。对2种材料在不同温度下,直流击穿特性和电导率与温度、场强的关系特性进行了对比分析。在30、50、70℃下,与1#试样直流击穿场强相比,2#试样的值分别提高了41.9%、22.8%和12.4%,直流击穿分散性随温度升高逐渐减小;材料电导率随温度升高逐渐增大;1#国产试样的性质随温度变化不发生改变,具有较好的稳定性;2种材料电导率随场强的变化存在"拐点",拐点处的场强随温度的升高而减小;当场强低于拐点的值时,电导率无明显变化;当场强高于拐点的值时,随场强升高而逐渐增大,并建立了场强高于拐点值时的电导率与温度和场强的函数关系式。

Through the analysis of curing reaction kinetics of domestic typical epoxy casting materials and foreign typical epoxy casting materials,the fast curing process parameters were got,and the validity of technological parameter was verified by the Tganalysis of cured epoxy resin.The DC breakdown characteristics and the conductivity of the two epoxy casting materials were analyzed under different temperature and field strength.The DC breakdown field strength of sample 1 was 41.9%,22.8%and 12.4%higher than that of sample 2 at 30,50 and 70℃,respectively.The dispersion of epoxy materials breakdown field strength got better with the increase of temperature,and the conductivity of epoxy materials increased with the temperature.The stability of sample 1 under different temperature was better.There was a"inflection point"in the conductivity of the two epoxy materials under different field strength.The field strength at the"inflection point"decreased with the increase of temperature,and the electric conductivity below the"inflection point"had no significant change,and the electric conductivity above the"inflection point"increased gradually with the increase of field strength.The functional relationship among the electric conductivity,the field strength and the temperature above the inflection point were established.