不同场强下新型绝缘聚合物的变色特性及其介电特性

Electrochromic and Dielectric Characteristics of Advanced Insulating Polymer under Various Electric Fields

为了依靠绝缘材料在电场下的颜色变化判断电力设备带电状态,制备了等规/无规聚(3-己基噻吩)(poly(3-hexylthiophene),P3HT)共混薄膜。研究发现,等规P3HT纳米微晶在共混薄膜顶部均匀分布。随无规P3HT含量的上升,共混薄膜沿厚度方向表现出更好的绝缘性能。在无规P3HT含量为95%时,共混薄膜的工频介电常数为5.86,电阻率为3.2 TΩ·cm,直流击穿场强达到113 kV/mm。通过空间电荷积累光谱发现,当电场强度大于40 kV/mm时,电荷主要积累在绝缘的无规P3HT中,且共混薄膜吸收光谱450 nm处峰强度随电场强度的增加而升高,实现了空间电荷驱动的绝缘体系电致变色,为电力设备绝缘带电状态检测提供了新方法。

In order to identify the charged states of power equipment through electrochromism of insulating materials,a regular/irregular poly(3-hexylthiophene)(reg-P3HT/irreg-P3HT)blend film is prepared.The experiment study shows that the reg-P3HT is evenly distributed as nano-scale crystallite morphology on top of the blend film.As the content of irreg-P3HT increases,the blend film shows better insulating performance in the direction of film thickness.When the content of irreg-P3HT reaches 95%,the blend film has a power frequency dielectric constant of 5.86,a volume resistivity of 3.2×10^(12)Ω·cm,and a DC breakdown strength of 113 kV/mm.By applying charge accumulation spectroscopy,it is found that when the field strength reaches over 40 kV/mm,the space charges mainly accumulate in irreg-P3HT,and the blend film’s absorption intensity increases with the field strength at 450 nm,triggering the electrochromism of the insulating film.This work provides a new path for testing the charged states of insulating materials of power equipment.