Catalytically active hybrid polyurethane with tetraaniline pendant groups: Synthesis, properties and self assembly

For the first time we report a novel hybrid polyurethane synthesized from tetraaniline-diol (TAni-(OH)(2)) and hexamethylene diisocyanate (HMDI) with pendant tetraaniline units on the back bone. The striking property of this unprecedented polyurethane is its electrochemical sensing of ascorbic acid and self assembly into core-shell type microstructures (microcapsules) in presence of aqueous acetic acid/n-octane interface. These microcapsules exhibited a wide range of pH responses in their absorption spectrum. The synthesized polyurethane containing pendant tetraaniline units showed good surface conductivity to the tune of 3.4 x 10(-4) S/cm. The electrochemical investigation showed two single electron oxidations and two single electron reductions reversibly. We also investigated electrochemical sensing details of carbon paste electrode (CPE) fabricated with conducting polyurethane (TANI-PU) as ascorbic acid sensor (vitamin C, AA) in 0.2 M and p(H) 7 phosphate buffer solution. The fabricated electrode is useful in sensing as low as 1 mM of ascorbic acid. Self-assembly property was probed by optical and TEM studies which established the core-shell structure of the assembled species. The self assembled microcapsules exhibited pH dependent doping and dedoping processes as established by UV-Vis study. (C) 2015 Elsevier Ltd. All rights reserved.