Preparation and properties of fluoroalkyl end-capped 2-acrylamido-2-methylpropanesulfonic acid oligomer/poly(vinyl alcohol) composite film

Fluoroalkyl end-capped 2-acrylamido-2-methylpropanesulfonic acid oligomer/poly(vinyl alcohol) composite [R-F-(AMPS)(n)-R-F/PVA] films were prepared by casting homogeneous aqueous methanol solutions containing R-F-(AMPS)(n)-R-F/PVA composites, which were prepared by the reactions of the corresponding oligomer with PVA. The transparent colorless R-F-(AMPS)(n)-R-F/PVA composite films thus obtained were subjected to tensile testing to evaluate the values of Young's modulus, tensile strength, and elongation at break. The R-F-(AMPS)(n)-R-F/PVA composites films are capable of greater Young's modulus than the original PVA film (PVA/HCl film), which was prepared by casting the aqueous methanol solution of PVA in the presence of 1 N hydrochloric acid. The polymer film bearing a higher Young's modulus is, in general, tough and brittle to providing lower elongation at break; however, we can observe a significant increase in both the tensile strength and elongation at break of the R-F-(AMPS)(n)-R-F/PVA composite films, compared to those of the PVA/HCl film. In addition, it was demonstrated that the R-F-(AMPS)(n)-R-F/PVA composite films can exhibit a higher water adsorption ability than that of the PVA/HCl film. Graphic abstract