writer：Juan Zhang, Andrew N. Keith, Sergei S. Sheiko,* Xuehui Wang,* and Zhigang Wang*
keywords：Bottlebrush, graft, block copolymer, skin property, mechanical property
source：期刊
specific source：ACS Appl. Mater. Interfaces 2021, 13, 3278?3286
Issue time：2021年

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.

KEYWORDS: bottlebrush copolymer, diblock copolymer side chains, microphase separation, cyclic tensile deformation, orientation