Unraveling the Gallol-Driven Assembly Mechanism of Thermoreversible Supramolecular Hydrogels Inspired by Ascidians

WOLFEL, ALEXIS; EUTI, ESTEBAN M.; PICCHIO, MATIAS LUIS; ROMERO, MARCELO RICARDO; GALVÁN JOSA, VÍCTOR; MARTINELLI, MARISA; MINARI, ROQUE J; ALVAREZ IGARZABAL, CECILIA INES

Polymer Chemistry

Royal Society of Chemistry

Lugar: London; Año: 2020

1759-9954

Polyphenol-based supramolecular hydrogels have recently attracted much attention as smart materials for applications in several technologies. Although great advances have been made in this field, there is a challenging need for creating new versatile materials that combine synthesis simplicity and suitable functional properties. In this work, inspired by the hydrogen bonding ability of pyrogallol-bearing proteins found in ascidians, we explored a small gallol-analog, gallic acid (GA), as a dynamic crosslinker of poly(vinyl alcohol) (PVA). Fundamentals of the supramolecular assembly mechanism of PVA/GA hydrogels are studied for understanding the final properties of the obtained thermo-reversible hydrogels. The polymer deacetylation degree was a key factor to control the gelation kinetics, morphology, and properties of the supramolecular materials. Furthermore, the intercalation of GA molecules between PVA chains produced polymer crystals with a new spatial arrangement, modifying the elastic modulus of the supramolecular network and increasing its stability in water. With remarkable fast gelation ability, ascidian-inspired PVA?GA hydrogels may provide a promising platform for a wide range of biomedical applications including topical drug delivery of therapeutic proteins, wearable electronic devices, and 3D-printing.