Astakhov E.Yu.,OOO NPP Ekspress Eko |
Zhironkin S.F.,OOO NPP Ekspress Eko |
Kolganov I.M.,OOO NPP Ekspress Eko |
Klinshpont E.R.,National Research Nuclear University |
Tsarin P.G.,OOO NPP Ekspress Eko
Polymer Science - Series A | Year: 2011
The mechanism of the phase separation of a poly(ester sulfone) solution induced by water vapor and further immersion in water is studied via the methods of electron microscopy and porometry. The effect of the one-side treatment of the solution resting on a support with water on the porous structure of the formed membrane is investigated. Exposure to water vapor sufficient for penetration across the entire thickness leads to formation of a membrane with a gradient porous structure and a selective layer at the side contacting water vapor. With an increase in the rate of water sorption in the interval from 70 to 550 g/(m2 h), the average pore size in the selective layer decrease from 170 to 70 nm. When a solution is treated with water vapor not through the entire thickness, a selective layer is formed inside the membrane. In this case, when the duration of treat- ment with water vapor decreases, the internal selective layer is shifted toward the side contacting water vapor. During instantaneous immersion in water, the selective layer is formed at the side contacting water and its pores are 20-30 nm in size. © Pleiades Publishing, Ltd., 2011.