Abstract
The swelling/shrinking behavior of chemically cross-linked poly(vinyl alcohol) (PVA) gel complexed with borate ions in aqueous medium and the intrinsic viscosity behavior of the corresponding polymer solutions were compared as a function of the boric acid concentration, b. The equilibrium swelling ratio of the gels, Q/Q 0 , and the intrinsic viscosity ratio of the solutions, [η]/[η] 0 , were in good accordance when the NaOH concentration, [NaOH], is high enough, where Q 0 and [η] 0 are the equilibrium swelling volume of the gel and the intrinsic viscosity of the solution without borate ions, respectively. NaOH was added so as to ionize boric acid. However, a significant difference was observed when [NaOH] was lowered. The comparison of Q/Q 0 and [η]/[η] 0 allowed one to elucidate the essential difference in the swelling (or expansion) behavior of polymer chains, which is the presence (in a gel) and absence (in a dilute polymer solution) of the Donnan potential. A free energy function for ion-complexed polymer gels is proposed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
