Methacryloxyethyl dimethyl n-hydroxyalkyl(C₂, C₃, C₆, C₈ and C₁₁) ammonium bromide monomers were prepared to be applied to the humid membrane. They were syringe coated onto the alumina substrate printed with gold electrode by photoinitiated polymrization and then the changes in electrical properties with humidity were measured. It was found that the impedance decreased with the increase of the thickness of the humid membrane. And also it was found that the impedance increased as the carbon chain of alkyl substituent in the monomer increased. For the humid membrane composed of 6-hydroxylhexyl substituent, the impedance was varied from 250KΩ to 1KΩ in the range of 30-90%RH. The temperature dependence coefficient for 15℃∼35℃ was found to be -0.5%RH/℃ and the hysterisis falled within the range of ±2%RH. The response time was found to be 35 seconds for varing humidity from 33% to 85%RH.

Methacryloxyethyl dimethyl n-hydroxyalkyl(C₂, C₃, C₆, C₈ and C₁₁) ammonium bromide 단량체들을 감습막으로 사용하기 위하여 제조하였다. 이들을 일루미나 기판위에 금으로 인쇄된 전극에서 광개시 중합에 의해 도포하였고 상대 습도 변화에 대한 전기적 성질을 측정하였다. 임피던스는 감습막의 두께가 증가할수록 감소하였으며 또한 단량체의 알킬 치환체의 탄소사슬이 길어질수록 증가하였다.% 6-Hydroxy hexyl 치환제로 이루어진 감습막의 임피던스는 30-90%RH범위에서 250KΩ에서 1KΩ까지 변하였다. 15∼35℃ 범위에서의 온도 의존상수는 -0.5%RH/℃이었으며 히스테리시스는 ±2%RH의 범위 안에서 나타났다. 응답속도는 33∼85 RH%의 사이에서 변화할 때 35초이었다.

Keywords: humid membrane; electrical properties; quarternized acrylate; impedence