Up/Down Tuning of Poly(ionic liquid)s in Aqueous Two-Phase Systems

Yuntao Tang; Yige Zhang; Xi Chen; Xiaowen Xie; Ning Zhou; Zhifeng Dai; Yubing Xiong

doi:10.1002/anie.202215722

Up/Down Tuning of Poly(ionic liquid)s in Aqueous Two-Phase Systems

Angew Chem Int Ed Engl. 2023 Jan 23;62(4):e202215722. doi: 10.1002/anie.202215722. Epub 2022 Dec 16.

Authors

Yuntao Tang¹, Yige Zhang¹, Xi Chen¹, Xiaowen Xie¹, Ning Zhou¹, Zhifeng Dai¹, Yubing Xiong¹

Affiliation

¹ Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang, 310018, China.

PMID: 36456527
DOI: 10.1002/anie.202215722

Abstract

Thermally induced reversible up/down migration of poly(ionic liquid)s (PILs) in aqueous two-phase systems (ATPSs) was achieved for the first time in this study. Novel ATPSs were fabricated using azobenzene (Azo)- and benzyl (Bn)-modified PILs, and their upper and lower phases could be easily tuned using the grafting degree (GD) of the Azo and Bn groups. Bn-PIL with higher GD_Bn could go up into the upper phase and Azo-PIL come down to the lower phase when the temperature increased (>65 °C); this behavior was reversed at lower temperatures. Moreover, a reversible two-phase/single-phase transition was realized under UV irradiation. Experimental and simulation results revealed that the difference in the hydration capacity between Bn-PIL and Azo-PIL accounted for their unique phase-separation behavior. A versatile platform for fabricating ATPSs with tunable stimuli-responsive behavior can be realized based on our findings, which can broaden their applications in the fields of smart separation systems and functional material development.

Keywords: Aqueous Two-Phase System; Phase Migration; Photo-Response; Poly(Ionic Liquid); Thermo-Response.

Abstract

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