Posted by Grafting poly(ethylene oxide-co-propylene oxide) chains onto a hyaluronan backbone (HA-PEPO) generates reversible thermoassociative properties characterized by low-viscosity liquid behaviour at low temperatures and gel formation above the transition temperature (20–25 °C) over a wide temperature range. Additionally, grafting adamantane units onto the same hyaluronan backbone (HA-ADA) enables host/guest coupling in the presence of poly(βcyclodextrin-co-epichlorhydrin) (poly(βCD-Ep). The complex formation between the two copolymers leads to the formation of a physical gel at low temperature that dissociates progressively and reversibly upon heating. While these two systems present antagonistic properties, we demonstrate that the double grafting of ADA and PEPO onto the same HA backbone (HA-ADA-PEPO) and its formulation with various amounts of poly(βCD-Ep) enables high viscoelastic properties to be maintained over a wide temperature range thanks to the superposition of these two interaction mechanisms. The molecular characteristics of these two association mechanisms and their independence from each other on the macroscopic properties of the formulations is analysed and discussed in detail combining rheology, calorimetry and neutron scattering measurements.
Supramolecular complex formation (Carsten Koopmans and Helmut Ritter (2008) Formation of Physical Hydrogels via Host−Guest Interactions of β-Cyclodextrin Polymers and Copolymers Bearing Adamantyl Groups. Macromolecules 2008 41 (20), 7418-7422. https://doi.org/10.1021/ma801202f)
Anne-Magali Layre, Carole Karakasyan, Lena Vincent, Theo Merland, Guylaine Ducouret, Clémence Le Coeur, Véronique Wintgens, Catherine Amiel, Dominique Hourdet (2026) Coupling of opposite thermoresponsive mechanisms induced by host-guest complexation and LCST phase transition in formulations of modified hyaluronan and β-cyclodextrin copolymer. Carbohydrate Polymers 377, 124862.
https://doi.org/10.1016/j.carbpol.2025.124862.