Composite Membrane Composed of Alaska Pollack Roe Membrane.

Abstract

We intended to show the structural change of the roe membrane in reply to the environmental change and propose a novel composite membrane with the roe membrane having the same response for the environmental change as the roe membrane. The roe membrane was prepared through thebreakage of the roe under shear and/or compression stress in 4 wt% NaCl aq. solution. The composite membrane with the roe membranes and calcium alginate or barium alginate was prepared by casting the aq. solution of the membranes and sodium alginate and then coagulating in the solution of CaCl2 or BaCl2, respectively. The molecular orientation in the roe membrane was evaluated using a polarization microscope and the transportation properties of the composite membrane were investigated under the dead end filtration. The roe membrane showed the reversible structural change in reply to the concentration of NaCl in water. The degree of the molecular orientation along the membrane surface took maximum at the NaCl concentration of ca. 3wt%. The membrane thickness increased with the concentration and the membrane was composed of at most eight layers. The composite membrane had reversible filtration rate with the change in the concentration of NaCl. The ratio between the membrane permeability of water and that of 4wt% of NaCl aq. solution was ca. 300 and the permeability depended on the preservation condition. These filtration characteristics diminished by the wet heat-treatment at higher temperature than 60°C. The composite membrane was expected to have the ability to respond to the change in the environmental condition as the case of the roe membrane.