Photoactivated nano-compatibilized two-phase polymer blends: an approach for determining mechanical behavior

Abstract

Light-activated polymers (LAPs) are shape-shifting materials capable of transforming their shapes in response to photoinduced chemical reactions, such as cis–trans isomerization and dimerization. Owing to the underlying photochemical reaction, these materials often exhibit behavior analogous to multicomponent/phase polymer blends. In this work, we present a free-energy-based theoretical framework to predict the mechanical behavior of nanoparticle-compatibilized elastic LAP blends that exhibit phase separation. In particular, we incorporate the impact of domain sizes and interfacial areas and establish a criterion for the materials’ susceptibility to mechanical failure under various loading conditions, namely uniaxial and biaxial stretching. Our framework can also be adapted to high-entropy polymers and thermoresponsive or light-activated systems, with potential applications in soft robotics, biomedical devices, micromechanics, 4D printing, and material origami. Additionally, by integrating our model with physics-informed neural networks, we facilitate efficient analysis of complex domain geometries and enable comprehensive parametric studies.