Effects of microstructure, crosslinking density, temperature and exterior load on dynamic pH-response of hydrolyzed polyacrylonitrile-blend-gelatin hydrogel fibers

The preparation of a smart hydrogel fiber based on hydrolyzed polyacrylonitrile-blend-gelatin is presented. The kinetics of the hydrogel fibers in response to pH change was reported. The effects of a number of factors were systematically studied, including the fiber diameter, concentration of crosslinker, environmental temperature and exterior load. The micro-morphology was also observed by SEM to verify the theoretical analysis. The experimental results revealed good consistence with Tanaka–Fillmore theory and Flory–Huggins theory, and it was found that the hydrogel fibers with high content of gelatin showed excellent and stable pH-response ability. Studies of dynamic elongation and contraction behaviors assist understanding and controlling of the pH-response of hydrogel fibers.