I used PI 2723 to fabricate a humidity sensor before.
Also you can try SU-8 2000.5 whose water absorption is 85% and dielectric
constant is 3.2.
It is good to be measured the capacitance change.
Lung-hao Hu
Graduate Student
Dept.of Mechanical Engineering
Univ.of Colorado Boulder
UCB 427 CO 80309 U.S.A
Email:[email protected]
Tel:303-786-1702(H)
303-492-6107(O)
Fax:303-492-3498