Intra-channel modification of environmentally sensitive poly(N-isopropylacrylamide) hydrogel with polyaniline using interphase synthesis

A new way of preparation of conducting gels by two-phase polymerization is presented. Polyaniline was introduced to the poly(N-isopropylacrylamide) hydrogel channels by filling the hydrogel first with a solution of the oxidazing agent and next placing it in a solution of aniline in nitrobenzene. It has been found, basing on optical, Raman and SEM investigations, that polyaniline was uniformly distributed in the entire gel samples and consisted mainly of emeraldine. The swelling behavior of obtained composite gels, in respect to a change in temperature and ionic strength, was very similar to unmodified poly(N-isopropylacrylamide) hydrogel. The new material appeared to be electroactive and conductive. This new property was a strong function of the swelling ratio. The shrinking process of the composite material considerably enhanced the voltammetric response.

We report on a new way of synthesis of electroactive environmental-sensitive hydrogel/conducting polymer composites based on two-phase polymerization strategy. Examination of morphology, swelling behavior and electrochemial properties of the conducting gel are shown.Figure optionsDownload as PowerPoint slideResearch highlights
► We fill the channels of poly(N-isopropylacrylamide) gel with polyaniline.
► A new specific two-phase polymerization is presented.
► The modified gel does not lose its environmental sensitivity.
► After filling with polyaniline the gel gets electroactivity and better conductivity.
► This new property is a strong function of the swelling ratio.