Selective permeability of PVA membranes. II. Heat-treated membranes

Abstract

SynopsisThe water and salt transport properties of untreated and heat-treated poly(viny1 alcohol) (PVA) membranes were investigated. Water and salt permeabilities decreased abruptly as a result of heat treatment. The effect of heat treatment on the water and salt transport in PVA is expressed mainly by changes in the activation energies of the corresponding permeability coefficients. Due to the fact that the decrease in the salt permeability with heat treatment was considerably greater than the decrease in the water permeability, a pronounced improvement in the salt rejection of PVA membranes was found as a result of heat treatment.

Immobilization of TiO2 nanoparticles in polymeric substrates by chemical bonding for multi-cycle photodegradation of organic pollutants

“…As a result, the photocatalytic activity of the composite photocatalysts is generally lower than that of TiO 2 suspended in aqueous solution. In comparison, the swelling ability of crosslinked PVA obtained by chemical [31,32,34] or physical [35,36] crosslinking methods, could provide the embedded TiO 2 particles with more opportunities to fully contact with organic pollutant in solution, which is favorable to the photocatalysis.…”

Polyvinyl alcohol as the barrier layer in thin film composite nanofiltration membranes: Preparation, characterization, and performance evaluation

“…The use of heat treated or formalized dense PVA film in desalination has been reported [12]. Greater swelling of PVA membrane in aqueous medium may lead to an open structure, which affects the membrane performance particularly the membrane rejection [13]. Hence there is a need to balance the hydrophilic and hydrophobic properties of such membranes, which may be achieved by cross-linking [14,15].…”

Comparison of Protein Fouling on Heat-Treated Poly(vinyl alcohol), Poly(ether sulfone) and Regenerated Cellulose Membranes Using Diffuse Reflectance Infrared Fourier Transform Spectroscopy

“…It has excellent chemical and thermal stability, and its semicrystalline structure contributes to its good mechanical strength. Methods have been developed to increase its mechanical strength including chemical cross-linking (22)(23)(24)(25)(26), irradiation (24,27), freezing and thawing techniques (28), and heat-treatment or annealing (29,30).…”