Photo-crosslinked thiol-ene based hybrid polymeric sensor for humidity detection

This study describes the preparation and characterization of new surface modified carbon nanotube particles (CNT) containing thiol-ene based hybrid polymers by photo-polymerization of pentaerythritol tetrakis, glyoxal bis(diallyl acetal), trimethylol propane triacrylate monomers and their usage for humidity sensing. CNT surface was photografted with polyethylene glycol acrylate (PEGA) to produce hydroxyl groups. Hydroxyl functionalized CNT/PEGAs were acrylated using isocyanatoethyl methacrylate (IEM) in order to improve the dispersion and interfacial interaction in composites. Furthermore, different amounts of gold nanoparticles containing compositions were also prepared. The humidity sensing properties of two samples were investigated by impedance measurements. The effects of CNT/Au modification, the applied potential bias and alternating current frequency on the electrical properties and the humidity sensitivity were determined. FCNT0 and FCNT5Au0.5 exhibit extremely high selectivity against humidity compare to various solvents; ethanol, acetone, methyl acetate and chloroform. FCNT0 has a reasonable good sensor performance for humidity measurements. It has high sensitivity, selectivity, stability, response/recovery and linear response properties in a full range of humidity measurements.