Surface graft polymerization of conducting polyaniline on waterborne poyurethane-urea film and its phenol sensing



Waterborne polyurethane-ureas (pristine WBPUs: WBPU-19 and WBPU-24, fixed soft segment content: 60 wt %) containing dimethylol propionic acid (DMPA)/ethylene diamine (EDA) contents (19/16.8 and 24/11.4 mol %) were prepared. The polyaniline (PANI)-graft-WBPU (PANI-graft-WBPU) films were prepared by oxidative graft polymerization of aniline on the surface layer of WBPU films. This study focused on the effects of reaction conditions (concentrations/treating times/temperatures of aniline and APS) and DMPA content on the %grafting, conductivity, and mechanical properties of PANI-graft-WBPU films. To obtain the maximum %grafting (PANI-graft-WBPU-19: 6.2, and PANI-graft-WBPU-24: 7.4) and conductivity (PANI-graft-WBPU-19: 3.6 × 10−2S/cm, and PANI-graft-WBPU-24: 4.7 × 10−2S/cm), the optimum concentrations/treating times/temperatures of aniline and APS, were found to be 0.35M/10 min/25°C and 0.2M/10 min/0°C, respectively. The tensile strength of film samples was found to be increased in the order of PANI-graft-WBPU-19>pristine WBPU-19>PANI-graft-WBPU-24>pristine WBPU-24. The PANI-graft-WBPU-19 (%grafting: 6.2) films on exposure to 0–10,000 ppm phenol solutions showed a well-defined response behavior, demonstrating high promise for application in aqueous phenol sensors. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013