To Mimic Mechanical Properties of the Skin by Inducing Oriented Nanofiber Microstructures in Bottlebrush Cellulose-graft-diblock Copolymer Elastomers

Skin is a vital biological defense system that protects the body from physical harm with its unique mechanical properties attributed to the hierarchical organization of the protein scaffold. Developing a synthetic skinlike material has aroused great interest; however, replication of the skin’s mechanical response, including anisotropic softness and strain-stiffening, is difficult to achieve. Here, to mimic the mechanical behaviors of skin, a reprocessable bottlebrush copolymer elastomer was designed with renewable and rigid cellulose as backbones; meanwhile, poly(n-butyl acrylate)-b-poly(methyl methacrylate) (PBA-b-PMMA) diblocks were designed as the grafted side chains. The so-made elastomers were subjected to a step-cyclic tensile deformation, by which the internal structures became oriented nanofibers and endowed stress–strain behaviors pretty much similar to those of the real skin. Overall, our research work currently undertaken would be of great importance in the development of a series of biomimetic skinlike polymer materials.