Polyethylenimine–polyepichlorohydrin interpolymer for chelating ion-exchange membrane

✍ Scribed by Takeo Saegusa; Akira Yamada; Shiro Kobayashi; Shinzo Yamashita

• Publisher: John Wiley and Sons
• Year: 1979
• Tongue: English
• Weight: 574 KB
• Volume: 23
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1979.070230812

✦ Synopsis

Polyethylenimine membranes consisting of linear polyethylenimine (PEI) and polyepichlorohydrin (PECH) were prepared by casting and heating an N,N-dimethylformamide solution of the two polymers under nitrogen at 100°C for 60 min. The membrane was also prepared by a heat-press method in a conventional manner. The cast membrane obtained was transparent. The membrane has a crosslinked structure due to the reaction between the secondary amino groups in PEI and the chloromethyl groups in PECH. Although a larger feed ratio of PEIPECH gave membranes with a larger adsorption capacity for Cu2+ ions, the optimum ratio was 40/100 with respect to mechanical properties. A belt conveyor system using the PEI membrane was able to transport Cu2+ ions from one bath to another. In a diffusion dialysis against 1N HCl, the PEI membrane crosslinked rather tightly showed a specific ion-selective transfer character. For example, in Cu2+-Ca2+ system the permeability ratio PcJPc, was about 3.8. The selectivity arises from the difference between affinities (extractabilities) of PEI toward metal ions. The selectivity was changed depending on the pH value.