Preparation of Bead-shaped Pullulan Ion Exchangers and Their Properties

Various bead-shaped pullulan ion exchange. rs were prepared from crosslinked bead-shaped pullulan. Diethyl-aminoethyl (DEAE) pullu-lan, 2-hydroxy-3-trimethylpropylammonio (HTMPA) pullulan, and 2-hydroxy-3- {2- [bis (2-hydroxyethyl) amino] ethoxy} propyl (ECTE0-LA) pullulan were prepared by reacting the crosslinked pullulan with N-2-chloroethyldiethylamine hydrochloride, N- (3-chloro-2-hydrox-ypropyl) trimethylammonium chloride, and a mixture of 2, 3-epoxypropyl chloride (epichlorohydrin) and 2, 2; 2′-nitrilotrisethanol (triethanol-amine), respectively. Their anion-exchange capacities and degrees of swelling were ca. 2.13, ca. 0.78, ca. 0.62 meq/g and ca. 10.0, ca. 6.5, ca. 8.5 cm3/g, respectively. Carboxymethyl (CM) pullulan and sulfomethyl (SM) pullulan were also prepared by reacting the crosslinked pullulan with chloroacetic acid and sodium chloromethanesulfonate, respectively. Their cation-exchange capacities and degrees of swelling were ca. 1.60, ca. 1.52 meq/g and ca. 11.0, ca. 5.8 cm3/g, respectively. Pullulan ion exchange beads obtained were found to be useful as packing materials for ion exchange chromatography.