Issue 7, 2023

Pre- and post-functionalization of thermoresponsive cationic microgels with ionic liquid moieties carrying different counterions

Abstract

Herein, we study the incorporation of hydrophilic-to-amphiphilic alkylated N-vinylimidazolium based ionic liquid monomers with different counter anions into N-vinylcaprolactam (VCL) based microgels via precipitation polymerization, and their resulting properties. Two strategies, following either a pre-functionalization of the comonomers by counterion exchange with subsequent polymerization, or post-functionalization via counterion exchange on pre-synthesized microgels, are applied and compared. The employed anions, i.e., halides (X), methanesulfonate (MeS), tetrafluoroborate (BF4), and bistriflimide (NTf2), were selected because of their kosmotropic-to-chaotropic solution properties. The resulting microgels with 10 mol% degree of functionalization were characterized by light scattering techniques, particularly with respect to their temperature-dependent swelling behavior and electrophoretic mobility. Differences in the counterion effect can be correlated to the solvation of the anions given by the Hofmeister series, cation–anion interaction strength, as well as the hydrophobicity of the vinylimidazolium moiety, i.e., the alkyl chain length. In this context, chaotropic anions will lead to a decrease in microgel size and electrophoretic mobility, while the volume phase transition temperature decreases as a function of the alkyl chain length. Moreover, the pre-functionalization approach can give access to different morphologies, such as anisotropic microgels, while generally restricting the microgel swelling, compared to the post-functionalization approach. Our results will allow for the controlled design of new functional microgels via simple precipitation polymerization with potential applications in drug delivery, biocatalysis and self-healing materials.

Graphical abstract: Pre- and post-functionalization of thermoresponsive cationic microgels with ionic liquid moieties carrying different counterions

Supplementary files

Article information

Article type
Paper
Submitted
30 ربيع الثاني 1444
Accepted
26 جمادى الثانية 1444
First published
04 رجب 1444

Polym. Chem., 2023,14, 848-861

Pre- and post-functionalization of thermoresponsive cationic microgels with ionic liquid moieties carrying different counterions

T. Belthle, M. Lantzius-Beninga and A. Pich, Polym. Chem., 2023, 14, 848 DOI: 10.1039/D2PY01477G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements