Oscillatory strain sweeps of hydrogels from methacrylated alginate macromonomers: Assessment of synthesis and acquisition variables

Abstract

The objective of this study is the rheological characterization of photocrosslinked alginate hydrogels synthesized from methacrylated alginate macromonomers. We first optimized the rheological acquisition parameters for this hydrogels, that is, we studied the influence of the geometries diameter, distance between plates (gap), and solvent trap in the rheological response. Our results show important variations of shear storage modulus, G', and yield strain with the three parameters measured. Secondly, with the optimized experimental parameters, rheological tests were performed on hydrogels synthesized under different conditions. Three parameters were studied; UV exposure time (polymerization time), macromonomer concentration and photoinitiator concentration. Our data indicate that the polymerization time and the macromonomer concentration have an important effect on the viscoelastic properties of the hydrogel, significantly modifying the shear storage modulus, G', and the yield strain while the photoinitiator concentration did not influence the viscoelastic properties.