聚酰亚胺/聚乙烯醇湿敏材料性能对比分析

湿度是仓储、民爆等领域一个重要的环境参量,湿敏材料感湿特性直接决定了传感器本身的性能优劣。选择光纤湿度传感器最常用的两种湿敏材料聚酰亚胺和聚乙烯醇作为研究对象,通过在光纤布拉格光栅表面涂覆两种不同的湿敏材料,分别对传感器的灵敏度、响应时间、长期稳定性进行测试。实验结果显示:涂覆聚酰亚胺的湿度传感器线性度可达99.98%,灵敏度为5.4 pm/%,响应时间为9.7 min,最大波长偏移量为5.6 pm;涂覆聚乙烯醇的湿度传感器在相对湿度60%~90%的高湿范围内具有更高的灵敏度,因此更适于高湿环境下的湿度测量。

Properties comparative analysis of polyimide/polyvinyl alcohol-based humidity-sensitive materials

Humidity is a significant environmental parameter in storage, civil explosives business, and other fields. The performance of humidity-sensitive materials directly determines the quality of sensors. Polyimide and polyvinyl alcohol, the most commonly used humidity-sensing materials in optical fiber humidity sensors, were selected as the research objects. The humidity sensors were fabricated by coating two different humidity-sensitive materials on the surface of the fiber Bragg grating and their sensitivity, response time, and long-term stability were tested and compared. Results show that the linearity of the humidity sensor coated with polyimide is 99.98%, the sensitivity is 5.4 pm/%, the response time is 9.7 min, and the maximum wavelength shift is 5.6 pm. The humidity sensor coated with polyvinyl alcohol has a higher sensitivity in the range of relative humidity 60%~90%, which makes polyvinyl alcohol-based humidity sensors more suitable for humidity measurement in high-humidity environments.