Humidity-Sensitive Properties of Polyelectrolytes Containing Alkoxysilane Crosslinkers

摘要

We have prepared new polyelectrolytes containing trialkoxysilyl groups by copolymerizing 3-(trimethoxysi-lyl)propyl methacrylate (TSPM) with either [2-(methacryloyloxy)ethyl]trimethyl ammonium chloride (METAC),[2-(methacryloyloxy)ethyl]dimethyl propyl ammonium bromide (MEDPAB),or [2-(acryloyloxy)ethyl]trimethyl ammonium chloride (AETAC).The copolymers TSPM/METAC,TSPM/MEDPAB,and TSPM/METAC having compositions of 15/85,10/90,and 5/95,respectively,were self-crosslinkable polyelectrolytes that possess humidity-sensitive properties.We measured the impedances of the copolymers at various relative humidities (RHs) and found that the resistance was dependent on the content of METAC,MEDPAB,or AETAC.The impedance changed from 107 Q at 20% RH to 103 Q at 95% RH,which is quite a suitable range for a humidity sensor that is to be utilized at ambient humidity.We also performed tests of the materials temperature dependence,hysteresis,response time,and water durability.