An ultrastrong bioinspired soy protein isolate-based nanocomposite with graphene oxide intercalation

Abstract

Soy protein isolate (SPI), a ubiquitous biopolymer , has attracted great attentions from scholars owing to its abundance, low cost and sustainability. However, the poor mechanical properties and low water-resistance have limited its applications. Therefore, there is a need to construct high-performance SPI-based materials. Inspired by the “brick-and-mortar” structures and interfacial interactions of nacre , a bioinspired nanocomposite was developed by intercalating graphene oxide (GO) nanosheets into the SPI-glycerin (Gly) matrix with a vacuum evaporation self-assembly technology. The obtained SPI-Gly-GO nanocomposite has shown enhanced tensile strength (18.60 ± 1.45 MPa) and modulus (275.68 ± 39.69 MPa), due to the hierarchical layered structures, and increased hydrogen bonds and covalent amido bonds. After chemical reduction, the SPI-Gly-rGO film possesses high tensile strength of 50.03 ± 2.67 MPa and high modulus of 1.7 ± 0.07 GPa, respectively, which are about 11.8 and 49.4 folds higher than that of the SPI-Gly film. Moreover, the resulting film maintains original morphologies after soaking in water for a long time, exhibiting excellent water-resistance, which is attributed to the interfacial interactions between rGO and SPI-Gly matrix. The fascinating integration characteristics enable the SPI-based materials to be used in food packages, tissue engineering, and gene delivery. The synthesis strategy provides new insights to design and fabricate high-performance SPI-based nanocomposite. A bioinspired nanocomposite, with integration of high mechanical properties and excellent water resistence, is fabricated by the synergy of hierarchical layered architectures and interfacial interactions. • A bioinspired nanocomposite based on SPI chains, Gly plasticizers andGO nanosheets is fabricated with an evaporation-induced assembly process. • The bioinspired nanocomposite is papared with the synergy of hierarchical layered architectures and interfacial interactions. • The resulting nanocomposite shows the integration of high mechanical properties and impressive water-resistance.