Intrinsic-water desorption induced thermomechanical response of hydrogels. Issue 43 (26th October 2022) - Debta, Sanghamitra
Abstract : Desorption of different types of water from the hydrogel at different temperature ranges resulting in different mechanical properties and relaxation behaviour. Abstract : We report an interplay between the desorption of intrinsic water and relaxation of polymer chains resulting in an unusual thermomechanical response of a hydrogel, wherein the elastic modulus increases in a certain temperature range followed by a sharp decrease with a further increase in temperature. We establish that, in a hydrogel, the desorption of disparate water types having distinct binding energy affects the consolidation and relaxation behaviour of the matrix, which in turn affects the mechanical properties at different temperature ranges. Using temperature-dependent dielectric relaxation spectroscopy and nanoindentation techniques, the chain dynamics and mechanical properties are investigated.