Naslov
Polimerne membrane
(Polymeric membranes)

Autori
Kunst, Branko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, ostalo

Izvornik
XIV. skup hrvatskih kemičara i IV. hrvatski simpozij o kemiji i tehnologiji makromolekula : sinopsisi / Janović, Zvonimir - Zagreb : Hrvatsko društvo kemijskih inženjera i tehnologa (HDKI) ; Hrvatsko kemijsko drustvo, 1995, 45-45

Skup
XIV. skup hrvatskih kemičara i IV. hrvatski simpozij o kemiji i tehnologiji makromolekula

Mjesto i datum
Zagreb, Hrvatska, 06.02.1995. - 08.02.1995

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
polimerne membrane; asimetrične membrane; fazna inverzija; priprava membrana; modeli; termodinamički uvjeti; kinetika formiranja membrana
(polymeric membranes; asymmetric membranes; phase inversion; membrane making process; model; thermodynamic conditions; kinetics of membrane making;)

Sažetak
A membrane, an intervening phase separating two fluid phases, plays a determining role in a transport of matter during membrane separation operations. As the membranes for both the separation operations and for the physicochemical studies are usually built of polymeric materials, their properties depend greatly on the proper choice of the polymer . Some recently redefined terms in membrane science are considered and leading membrane separation operationa are reviewed. Two important discoveries in the last 50 years, ion exchange membranes and asymmetric membranes are refered to with a special attention given to the latter. The asymmetric membranes are most often prepared by the phase inversion technique. The effect is induced in a cast polymer solution layer by solvent evaporation or by immersion in a nonsolvent. The sequence of ensuing events produces a multilayered membrane with layers of different morphologies and porosities. The membrane making process cannot be followed by direct measuring, SEM micrographs display only structure of supporting layer(s). Therefore the phase inversion process has also been modelled. A theoretical approach includes both thermodynamic and kinetic aspects of the process. The first part of the analysis, a ternary phase diagram construction, is followed by defining and solving diffusion equations enabling eventually the calculation of a "composition path" of the cast polymer solution during a demixing step. The procedure with addition of some new ideas on formation of a "defect-free" skin, is presented.

Izvorni jezik
Hrvatski

Znanstvena područja
Kemija

POVEZANOST RADA