Development of Quaternized Chitosan Integrated with Nanofibrous Polyacrylonitrile Mat as an Anion-Exchange Membrane

Aktilek Akhmetova; Bauyrzhan Myrzakhmetov; Yanwei Wang; Zhumabay Bakenov; Almagul Mentbayeva

doi:10.1021/acsomega.2c05961

Development of Quaternized Chitosan Integrated with Nanofibrous Polyacrylonitrile Mat as an Anion-Exchange Membrane

ACS Omega. 2022 Nov 30;7(49):45371-45380. doi: 10.1021/acsomega.2c05961. eCollection 2022 Dec 13.

Authors

Aktilek Akhmetova¹, Bauyrzhan Myrzakhmetov², Yanwei Wang^{1

2}, Zhumabay Bakenov^{1

2}, Almagul Mentbayeva¹

Affiliations

¹ Department of Chemical and Materials Engineering, School of Engineering and Digital Sciences, Nazarbayev University, Nur-Sultan010000, Kazakhstan.
² Center for Energy and Advanced Materials Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan010000, Kazakhstan.

Abstract

A two-phase anion-exchange membrane was prepared from quaternized chitosan (QCS) integrated with an electrospun polyacrylonitrile (PAN) scaffold by spin coating. To synthesize QCS, glycidyltrimethylammonium chloride in various amounts was introduced into the structure of CS. The characterization of the cast cross-linked QCS (CQCS) membranes by impedance spectroscopy revealed the ionic conductivity (IC) in the range of 2.8 × 10^-4 to 8.2 × 10^-4 S cm^-1 and the degree of quaternization (DQ) of 26.4-51.0%, where the CQCS film with the DQ of 51.0% showed excellent performance. When CQCS was reinforced with a PAN fiber mat, the newly developed composite membrane demonstrated the highest IC of 34 × 10^-4 S cm^-1 at 80 °C, low swelling, and an almost eightfold increase in tensile strength at a fully hydrated state compared to pristine materials. Moreover, the CQCS/PAN membrane was chemically stable and revealed increasing hydroxide transport during 1 month immersion in alkaline media.