A water durable resistive humidity sensor based on rigid sulfonated polybenzimidazole and their properties

作者：Park Kwang Jin; Gong Myoung Seon^*

来源：Sensors and Actuators B: Chemical , 2017, 246: 53-60.

DOI：10.1016/j.snb.2017.02.074

• Humidity sensor
• Sulfonated polybenzimidazole
• Rigid structure
• Water durability
• Anchoring

A water-durable, polymeric resistive humidity sensor was designed using rigid sulfonated polybenzimidazole (SPBI) with tetramethylammonium (Me4N+) as the counter cation. The Me4N-SPBI structure based on the imidazole group was used to obtain a cross-linkable moiety to attach the humidity sensitive polyelectrolyte film to an alumina substrate pretreated with an aminosilane coupling agent using an epoxy cross-linker. The SPBI in Me4N+ structure is derived from 3,3'-diaminobenzidine (DAB), sodium 6,6'-oxybis(3-carboxybenzenesulfonate) (SOCBS) and 4,4'-oxybisbenzoic acid (OBBA), followed by quaternization, which allows for easy fabrication, higher sensitivity and better adhesion between the film and the substrate. The effect that cross-linking and anchoring the Me4N-SPBI films had on the humidity-sensing properties and water durability of sensors were investigated. The SPBI films with Me4N-DAB/SOCBS/OBBA= 100/100/0 and 100/70/30 exhibited a linear response with a resistivity of 6.11-1.19 k Omega and 7.60 M Omega-2.51k Omega between 20 and 95% RH, respectively. Consequently, cross-linking and anchoring the film to the substrates with a coupling reagent significantly improves the water durability and stability at a high humidity and high temperature.

• 出版日期2017-7