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arXiv · 1611.07721

Ion pairing controls rheological properties of "processionary" polyelectrolyte hydrogels

Hassan Srour·Martien Duvall Deffo Ayagou·Thi Thanh-Tam Nguyen·Nicolas Taberlet·Sébastien Manneville·Chantal Andraud·Cyrille Monnereau·Mathieu Leocmach
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Abstract

We demonstrated recently that polyelectrolytes with cationic moieties along the chain and a single anionic head are able to form physical hydrogels due to the reversible nature of the head-to-body ionic bond. Here we generate a variety of such polyelectrolytes with various cationic moieties and counterion combinations starting from a common polymeric platform. We show that the rheological properties (shear modulus, critical strain) of the final hydrogels can be modulated over three orders of magnitude depending on the cation/anion pair. Our data fit remarkably well within a scaling model involving a supramolecular head-to-tail single file between cross-links, akin to the behaviour of pine-processionary caterpillar. This model allows the quantitative measure of the amount of counterion condensation from standard rheology procedure.

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Hassan Srour, Martien Duvall Deffo Ayagou, Thi Thanh-Tam Nguyen, Nicolas Taberlet, Sébastien Manneville, Chantal Andraud, Cyrille Monnereau, Mathieu Leocmach. 2016-11-23. Ion pairing controls rheological properties of "processionary" polyelectrolyte hydrogels. https://doi.org/10.1039/c6sm02022d

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