Related Experiment Video
Updated: Oct 30, 2025

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device
Published on: July 20, 2021
Ionic Transport Properties of Cation-Exchange Membranes Prepared from Poly(vinyl alcohol-b-sodium Styrene Sulfonate)
Yuriko Kakihana1,2, N Awanis Hashim3, Taiko Mizuno1
1Graduate School of Sciences and Technology for Innovation, Yamaguchi University, 2-16-1 Tokiwadai, Ube Yamaguchi 755-8611, Japan.
Abstract:
Membrane resistance and permselectivity for counter-ions have important roles in determining the performance of cation-exchange membranes (CEMs). In this study, PVA-based polyanions-poly(vinyl alcohol-b-sodium styrene sulfonate)-were synthesized, changing the molar percentages CCEG of the cation-exchange groups with respect to the vinyl alcohol groups. From the block copolymer, poly(vinyl alcohol) (PVA)-based CEMs, hereafter called "B-CEMs", were prepared by crosslinking the PVA chains with glutaraldehyde (GA) solution at various GA concentrations CGA. The ionic transport properties of the B-CEMs were compared with those previously reported for the CEMs prepared using a random copolymer-poly(vinyl alcohol-co-2-acrylamido-2-methylpropane sulfonic acid)-hereafter called "R-CEMs". The B-CEMs had lower water content than the R-CEMs at equal molar percentages of the cation-exchange groups. The charge density of the B-CEMs increased as CCEG increased, and reached a maximum value, which increased with increasing CGA. A maximum charge density of 1.47 mol/dm3 was obtained for a B-CEM with CCEG = 2.9 mol% and CGA = 0.10 vol.%, indicating that the B-CEM had almost two-thirds of the permselectivity of a commercial CEM (CMX: ASTOM Corp. Japan). The dynamic transport number and membrane resistance of a B-CEM with CCEG = 8.3 mol% and CGA = 0.10 vol.% were 0.99 and 1.6 Ωcm2, respectively. The B-CEM showed higher dynamic transport numbers than those of the R-CEMs with similar membrane resistances.
Related Concept Videos
Ion Exchange
Pore Transport and Ion-Pair Transport
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct...
The Significance of Membrane Transport
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
Potentiometry: Membrane Electrodes
Ion-Exchange Chromatography
Facilitated Diffusion
In this process, substrates such as organic compounds and ions interact with a transporter on one side, triggering conformational changes in proteins that enable...

