Thermo- and pH-sensitive gel membranes based on poly-(acryloyl--proline methyl ester)--poly(acrylic acid) for selective permeation of metal ions

Hasegawa, Shin; Ohashi, Hitoshi; Maekawa, Yasunari; Katakai, Ryoichi*; Yoshida, Masaru

Thermo- and pH-responsive gel membranes were synthesized by -ray grafting of pH-responsive poly (acrylic acid) (AAc) onto thermo-responsive polymer gel of acryloyl--proline methyl ester (A-ProOMe). The gel membranes of poly (A-ProOMe) with 15 mol% graft chains of AAc exhibited both thermo- and pH-responses. Under the condition (pH 6.0, 30C) in which the thermo-sensitive unit shrinks and the pH-sensitive unit swells, the selective permeation of Li ion over Co and Ni ions can be achieved.