Mechanical relaxation of glassy gelatin films

The structural relaxation during the ageing of glassy gelatin films containing 8, 12 and 17 % water at 25°C was studied through the changes in storage modulus (E’) measured isothermally in bending mode at different frequencies using DynamicMechanical Thermal Analysis (DMTA). The E’ increased with increasing ageing time (ta) and measurement frequency. Forall the water contents, the rates of ageing were extracted though time - ageing time superposition of E’ data. The rate andextent of ageing increased with water content.

Keywords:

gelatin , mechanical relaxation , time - ageing time superposition , physical ageing , storage modulus