Mesoscale characterization of supramolecular transient networks using SAXS and rheology.
Hydrogels and, in particular, supramolecular hydrogels show promising properties for application in regenerative medicine because of their ability to adapt to the natural environment these materials are brought into. However, only few studies focus on the structure-property relationships in supramolecular hydrogels. Here, we study in detail both the structure and the mechanical properties of such a network, composed of poly(ethylene glycol), end-functionalized with ureido-pyrimidinone fourfold hydrogen bonding units. This network is responsive to triggers such as concentration, temperature and pH. To obtain more insight into the sol-gel transition of the system, both rheology and small-angle X-ray scattering (SAXS) are used. We show that the sol-gel transitions based on these three triggers, as measured by rheology, coincide with the appearance of a structural feature in SAXS. We attribute this feature to the presence of hydrophobic domains where cross-links are formed. These results provide more insight into the mechanism of network formation in these materials, which can be exploited for tailoring their behavior for biomedical applications, where one of the triggers discussed might be used.
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. a.c.h.pape@tue.nl.
A C H
AC
Pape
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. maartje.bastings@gmail.com.
Maartje M C
MM
Bastings
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. r.e.kieltyka@chem.leidenuniv.nl.
Roxanne E
RE
Kieltyka
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. h.m.wyss@tue.nl.
Hans M
HM
Wyss
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. i.voets@tue.nl.
Ilja K
IK
Voets
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. e.w.meijer@tue.nl.
E W
EW
Meijer
Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, Eindhoven, The Netherlands. p.y.w.dankers@tue.nl.
Patricia Y W
PY
Dankers
D020100:Hydrogels / Q000737:chemistry*; D006860:Hydrogen Bonding; D011092:Polyethylene Glycols / Q000737:chemistry; D011744:Pyrimidinones / Q000737:chemistry; D012212:Rheology; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction
D020100:Hydrogels; D011744:Pyrimidinones; D011092:Polyethylene Glycols