Cationic membranes of poly(chloromethylstyrene-co-divinyl benzene) having quaternary ammonium groups with different alkyl chains, such as triethyl, tri-n-butyl and tri-n-octyl groups, were prepared. The effects of diluent and introdced amine group on the morphology, membrane charateristics and performance such as fixed charge density, salt permeability, sorption behavior, were investigated. For the permeation and sorption experiment, sodium halides (NaCl, NaBr, NaI) and nitrate (NaNO₃) were used as the salts. The permeabilities of the membranes showed minima at relatively low upstream salt concentrations, and were not of a simple Donnan exclusion type. These results, together with the sorption isotherms, were explained by assuming two sorption and permeation modes, i.e., partition under the Donnan exclusion and the Langmuir type. As the porosity in the membrane increased. the permeability and the sorption of the salts as well as density and water content of water-swollen membrane increased. And as the alkyl chain length of quaternary ammonium groups in the membrane increased, water content decreased because of increasing hydrophobicity of the membrane, while the sorption of salts increased.

4급 암모늄기가 도입된 poly(chloromethylstyrene-co-divinyl benzene) 양이온막을 제조하였으며, 막 제조시의 기공형성제 함량과 도입된 아민기의 alkyl spacer의 길이가 막의 molphology, 고정하전밀도, 염투과 및 수착 등의 막특성 및 막기능에 미치는 영향을 조사하였다. 투과 및 수착실험에는 NaCl, NaBr, NaI 및 NaNO₃ 등의 Na염을 사용하였다. 막의 염투과는 저농도에서 염농도가 증가함에 따라 투과계수가 감소하여 투과계수의 극소치가 나타났는데, 이러한 거동은 단순한 TMS이론과 일치하지 않아 Donnan 배제와 Langmuir형이 혼합된 형태로써 설명하였다. 연구의 결과 막 내의 porosity가 증가함에 따라 막의 밀도, 함수율 그리고 투과계수 및 수착량이 증가하였고, 도입된 4급 암모늄기의 alkyl chain의 길이가 증가함에 따라 수착량은 증가하였으나 막의 소수성이 커져 함수율은 감소하였다.

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