TY  - JOUR
A1  - Neffe, Axel T.
A1  - Löwenberg, Candy
A1  - Lendlein, Andreas
T1  - Hydrogel networks by aliphatic dithiol Michael addition to glycidylmethacrylated gelatin
T2  - MRS advances : a journal of the Materials Research Society (MRS)
N2  - Functionalization of gelatin with glycidylmethacrylate (GMA-gelatin) enables network formation employing the double bond, so that the reaction is orthogonal to the inherent functional groups in the biomacromolecule. Here, network formation by crosslinking of GMA-gelatin with hexane 1,6-dithiol or nonane 1,9-dithiol to tailor properties and enable a shape-memory effect is shown by H-1 NMR and FT-IR spectroscopy. Hydrogel swelling (460-1900 vol%) and mechanical properties (Young's modulus E = 59-512 kPa, elongation at break epsilon(b) = 44-127%) depended on the molecular composition of the networks and temperature. Increased crosslinker length, thiol:methacrylate molar ratio, and precursor concentrations led to denser networks. Change of properties with temperature suggested adoption of triple helices by gelatin chains, forming physical netpoints at lower temperatures (< 20 degrees C). However, the limited freedom of the gelatin chains to move allowed only a minimal extent of triple helices formation, as it became apparent from the related signal in wide-angle X-ray scattering and the thermal transition associated to triple helices in some networks by DSC. The presented strategy is likely transferable to other biomacromolecules, and the results suggest that too short crosslinkers may result in a significant amount of grafting rather than network formation.
Y1  - 2021
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/62736
SN  - 2059-8521
VL  - 6
IS  - 33
SP  - 796
EP  - 800
PB  - Springer Nature Switzerland AG
CY  - Cham
ER  -