Circumferential buckling of a hydrogel tube emptying upon dehydration

Abstract A cylindrical hydrogel tube, completely submerged in water, hydrates by swelling and filling its internal cavity. When it comes back into contact with air, dehydrates: the tube thus expels solvent through walls, shrinking. This dehydration process causes a depression cavity, which can lead to circumferential buckling. Here we study occurrence of such buckling using continuous model that combines nonlinear elasticity Flory–Rehner theory, take account both large deformations active behaviour hydrogel. In quasi-static approximation, use incremental deformation formalism, extended chemo-mechanical equations, determine threshold value enclosed volume at is triggered. critical found depend on shell thickness, chemical potential constitutive features. The results obtained are good agreement finite element simulations complete dynamic problem.