Preparation, morphology and pH sensitivity of hybrid hydrolyzed polyacrylonitirile‐blend‐gelatin hydrogel fibers

Abstract

AbstractBACKGROUND: Polyacrylonitrile (PAN) artificial muscles have attracted considerable attention for their fast responses. This research work is based on the preparation of novel pH‐sensitive hydrogel fibers derived from hydrolyzed PAN and gelatin by wet spinning and chemical modification.RESULTS: Through characterization of the fiber dynamic and static pH‐sensitive behavior, pH response times were found to improve greatly with increasing gelatin content. At a weight ratio of 3 to 7 (PAN:gelatin), the best response times were obtained at 0.59 s for elongation and 1.14 s for contraction. Study of the chemical structures of hydrolyzed PAN and gelatin, as well as the surface morphology of the hydrogel fibers, indicated that the mechanism of formation of hydrogel fibers is closely interconnected with their pH‐sensitive behavior. From the standpoint of the mechanism we also found that the addition of urea gave rise to hydrogel fibers with a controllable morphology, influenced by the pH‐sensitive behavior.CONCLUSION: The hydrogel system reported here is simple in preparation, but quite complex in chemical structure. The strong response of the fibers to pH provides some idea on the development of new artificial muscle systems. Copyright © 2008 Society of Chemical Industry