Analysis of solute diffusion in poly(vinyl alcohol) hydrogel membrane

• Published in: Journal of membrane science Vol. 126; no. 1; pp. 151 - 160
• Main Authors: Matsuyama, Hideto, Teramoto, Masaaki, Urano, Hiroshi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02.04.1997; Elsevier
• Subjects: Applied sciences; Composites; Exact sciences and technology; Forms of application and semi-finished materials; Free volume theory; Hydrogels; Lysozyme; Partition coefficient; Poly(vinyl alcohol); Polymer industry, paints, wood; Technology of polymers; Poly(vinyl alcohol); Partition coefficient; Hydrogels; Free volume theory; Lysozyme; Polyvinylalcohol; Lysosome; Free volume; Membrane; Hydrogel; Diffusion
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/S0376-7388(96)00287-6

Measurement of diffusion and partitioning of solutes having molecular weights ranging 180–66000 in PVA gel membranes with various crosslinking degree were carried out. With increasing solute size or decreasing number of average molecular weight between crosslinks of the membranes, both the solute permeability and partition coefficient decreased. In spite of similar solute sizes, the more hydrophilic solute ribonuclease showed higher permeability and partition coefficient than the less hydrophilic α-lactalbumin, probably due to interaction with the hydrophilic PVA. The solute diffusion through swollen gel membrane was analyzed by the equation based on free volume theory. In this analysis equation, the partition coefficient, which is defined as the ratio of solute concentration in gel membrane standardized by water volume in the membrane to that in bulk solution, was introduced as the probability of a diffusing species finding a mesh with a volume of at least the solute size. The efficiency of the proposed analysis equation was confirmed by the experimental results of the effects of solute size and water volume fraction in the membrane.