Morphing of soft structures driven by active swelling: a numerical study

The study aims to highlight the differences between growth-by-diffusion, based on the elastic stretch of the polymeric network, and growth-by-activity, based on the remodeling of the network, in polymer gels. The study is based on a multiphysics continuum model, which allows to describe the interactions between mechanics, diffusion and growth through a system of nonlinear partial differential equations. We discuss the differences between growth-by-diffusion and growth-by-activity and evidence the role of the corresponding characteristic times in the case of homogeneous activation source. We also show as a huge variety of three-dimensional shapes can be generated by controlling the distribution of the activation sources.