Our latest preprint, “Thermodynamics of microphase separation in a swollen, strain-stiffening polymer network“, led by Carla Fernández-Rico(a former postdoc) and Rob Style (ETH), is now available on arXiv!

Bicontinuous materials feature fascinating properties, and are found acrooss scales in nature. For instance, bicontinuous photonic structures in bird feathers produce beautiful structural colors. Owning to its unique topology and large surface area, bicontinuous materials have inspired the development of efficient catalyssis, energy storage, and optical and mechanical metamaterials.

Elastic MicroPhase Separation (EMPS) provides a simple route to create soft materials with bicontinuous microstructure. Conceptually, this method leverages elasticity of the material to tune the emerging lengthscale. (Read more on our Nature Materials Article about EMPS.)

In this preprint, Carla and Rob investigate the thermodynamics of EMPS. They extend Flory–Huggins theory by incorporating strain-stiffening effects, enabling prediction of EMPS phase diagrams without fitting parameters. The model depends only on experimentally measurable quantities—solubility parameters and large-deformation mechanical responses—and it matches experiments remarkably well. This work offers a solid foundation for EMPS-based material design, presents testable hypotheses, and will guide further experi

mental studies!