Physical Polyurethane Hydrogels via Charge Shielding through Acids or Salts

Mai-Thi Leiendecker; Christopher J Licht; Jannik Borghs; David J Mooney; Marc Zimmermann; Alexander Böker

doi:10.1002/marc.201700711

Physical Polyurethane Hydrogels via Charge Shielding through Acids or Salts

Macromol Rapid Commun. 2018 Apr;39(7):e1700711. doi: 10.1002/marc.201700711. Epub 2018 Jan 31.

Authors

Mai-Thi Leiendecker^{1

2}, Christopher J Licht³, Jannik Borghs³, David J Mooney⁴, Marc Zimmermann^{1

2}, Alexander Böker^{1

2}

Affiliations

¹ Fraunhofer Institute for Applied Polymer Research (IAP), Geiselbergstr. 69, 14476, Potsdam-Golm, Germany.
² Lehrstuhl für Polymermaterialien und Polymertechnologie, Universität Potsdam, 14476, Potsdam, Germany.
³ Insitute of Organic Chemistry, RWTH Aachen University, Templergraben 55, 52062, Aachen, Germany.
⁴ John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.

PMID: 29383857
DOI: 10.1002/marc.201700711

Abstract

Physical hydrogels with tunable stress-relaxation and excellent stress recovery are formed from anionic polyurethanes via addition of acids, monovalent salts, or divalent salts. Gel properties can be widely adjusted through pH, salt valence, salt concentration, and monomer composition. We propose and investigate a novel gelation mechanism based on a colloidal system interacting through charge repulsion and chrage shielding, allowing a broad use of the material, from acidic (pH 4-5.5) to pH-neutral hydrogels with Young's moduli ranging from 10 to 140 kPa.

Keywords: acidic crosslinking; charge repulsion; charge shielding; ionic crosslinking; physical hydrogels; polyurethanes; stress recovery; stress-relaxation.

MeSH terms

Elastic Modulus*
Hydrogels / chemistry*
Hydrogen-Ion Concentration
Polyurethanes / chemistry*

Substances

Hydrogels
Polyurethanes