Environmentally sensitive hydrogel functionalized with electroactive and complexing‐iron(III) catechol groups

Thermoresponsive pNIPA (poly (N‐isopropylacrylamide)) gels modified with dopamine methacrylamide were synthesized using free‐radical polymerization. In this way, the catechol groups were introduced into the polymer network. The presence of dopamine in the gel led to a significant shift in the volume phase transition temperature (VPTT). It was found that hydrogels were electroactive and that oxidation of catechol groups also led to a strong shift in the VPTT. The temperature window, that is, the range of temperature where volume of the gel could be substantially changed by oxidation of the catechol groups, for the gel formed from the polymerization solution containing 5% of the dopamine derivative, was 30–40 °C. Additionally, the influence of Fe³⁺ ions, which form the most stable complexes with dopamine, on swelling behavior of the gels was investigated at various pH. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3236–3242