Construction of chitin nanocrystal/poly(deep eutectic solvent) elastomers via glycidyl methacrylate associated modification, polymerization and crosslinking for artificial skin applications

A one-pot strategy was developed to fabricate a strong and ductile elastomer composed of chitin nanocrystals and poly(deep eutectic solvent) (ChNC/PDES), based on a dual-network structure formed through glycidyl methacrylate (GMA)associated modification, polymerization and crosslinking. This approach enables the integrated pretreatment, chemical modification, and nanodispersion of chitin within a lactic acid/choline chloride deep eutectic solvent (DES) system. Whereafter, the ultraviolet initiated polymerization of GMA with ChNC and DES components produced a homogeneous elastomer with a maximum tensile strength of 4.50 MPa and an elongation at break of 890 %. The mechanical performance was regulated by the degree of deacetylation (DDA) and aspect ratio of ChNC: higher DDA provided more amino groups for crosslinking and enhanced ductility, whereas it also reduced elastomer stiffness due to smaller nanocrystal size. Furthermore, a spin-coating and alcohol-water rinsing protocol enabled the fabrication of ultrathin elastomer films (~0.25 mm thick) that adhered conformably to human skin and accommodated complex deformations. These findings demonstrate the potential of bio-based ChNC/PDES elastomers as sustainable and flexible candidates for artificial skin applications.