Study On PH-sensitive Behavior Of Intelligent Fiber Based On Polymers Of Acrylonitrile And Acrylic Acid

Polyacrylic acid pH-sensitive gels as an important smart material iswidely used for drug delivery enzyme immobilization material separationchemical mechanics and so on. One component polyacrylic acid with lowstrength, even can't be prepared. The polymer [P (AN-co-AA)] based on PANand PAA combined appropriately, has desirable mechanical properties andpH-sensitivity.In this paper, chemical structure of the copolymers P (AN-co-AA) canbe adjusted by two feeding ways. Fiber produced by wet spinning of polymersolution with fine chemical structure, was discussed for pH-sensitive behavior.Effects of physical configuration on pH sensitive performance of the fiberwere investigatedThe results show that copolymers by batch feed method have excellentpH-sensitivity and mechanical properties. Fibers produced polymer solutionby batch feed method have pH-sensitive hysteresis loop behavior andreversible swelling-deswelling behavior. Response rates is larger in0.1mol/Lacid than in0.1mol/L alkali solutions. Swelling ratio of fiber is related tocrystalline structure. High crystallinity, orientation of molecule chains, less molecule chains distance, strong molecular interactions, may result strongconfinement on fiber, which makes swelling ratio poor. Response time of fiberis related to pore structure and diameter and so on. The larger surface area offiber pores, the less response time; short transmission distance for smalldiameter of fiber, which makes response time decreased; pore structureinfluences response time greater.