Evaluation of a Thermochromic Liquid Crystal for Use as a Temperature Sensor for Components of Electrical Systems

Connectors used in electrical power distribution systems should allow the passage of electricity continuously and without interruption. However, this does not always occur due to failure caused by improper assembly and/or corrosion of the materials employed, which reflects the quality of service. Notable among the new detection technologies that have been studied to facilitate the identification of defects is the use of thermochromic materials, which allow the easy identification of "hot spots", without the need for specialized equipment and personnel. In this context, in this study, the performance of a thermochromic liquid crystal was evaluated with the aim of developing a temperature sensor for connectors used in electrical power distribution networks. For the evaluation of the performance, thermal and ultraviolet radiation degradation tests were conducted, as well as analysis using spectroscopic (FTIR, FTIR-HATR, UV-Vis, 1H NMR) and thermal (DSC, PLM) techniques. The results indicated that the liquid crystal and the associated components showed no degradation under the test conditions, as well as a good color stability was observed, verifying the viability of the use of these materials for the construction of a temperature sensor. A field test was performed with the devices and was effective for the suggested application.

用于配电系统的连接器应能持续、不间断地导通电流。然而，受装配不当及/或所用材料腐蚀引发的故障影响，这一目标并非总能达成，该问题也侧面反映了服务质量水平。为便于缺陷识别，已有诸多新型检测技术得到研究，其中热致变色材料（thermochromic materials）的应用尤为突出——这类材料无需专用设备与专业人员即可轻松识别“热点”。在此研究背景下，本研究对一款热致变色液晶的性能展开评估，以期开发一种适用于配电网络连接器的温度传感器。为验证其性能，本研究开展了热与紫外辐射降解试验，并采用光谱技术（傅里叶变换红外光谱（FTIR）、傅里叶变换红外衰减全反射（FTIR-HATR）、紫外-可见分光光度法（UV-Vis）、核磁共振氢谱（1H NMR））与热分析技术（差示扫描量热法（DSC）、偏光显微镜法（PLM））进行表征。结果显示，该液晶及其相关组分在试验条件下未发生降解，且表现出良好的色彩稳定性，证实了此类材料用于构建温度传感器的可行性。针对该装置开展的现场试验结果表明，其可有效满足所提议的应用需求。