Preparation of isocyanate functionalized graphene oxide/thermoplastic polyurethane elastomer nanocomposites and their antistatic properties

Graphene oxide (GO) was functionalized with 4, 4-diphenylmethane diisocyanate (MDI), to obtain the graphene oxide (GO-MDI) with isocyanate group (  NCO). The thermoplastic polyurethane elastomers (TPU)/GO composites with antistatic properties were synthesized by in-situ polymerization with polycarbonate diol (PCDL), MDI and GO-MDI as raw materials. The surface resistance of the material was tested, revealing that the surface resistance of the material was reduced from more than 1 × 10 12 Ω to 6.67 × 10 9 Ω when the GO addition was only 0.25 wt%. With the increase of GO addition, the surface resistance showed a trend of continuous decrease, and, it dropped to 3.33 × 10 7 Ω when the GO content was 1 wt%, which significantly improved its antistatic performance. The addition of GO not only improved the antistatic ability of the material, but also enhanced its mechanical and thermal properties. Especially for the tensile strength and elongation at break, when the amount of graphene oxide was 0.5 wt%, the tensile strength and elongation at break of TPU were 60% and 16% higher than that of pure TPU, respectively. Although the tensile strength and elongation at break decreased when GO addition exceeded 0.5 wt%, they were still higher than that of pure TPU. The glass transition temperature and thermal decomposition temperature of the material increased with the increase of GO addition, and the maximum increase was 1–7 °C. The energy storage modulus ( E ′) at low temperatures increased from 1848 MPa of pure TPU to 2353 MPa of GO 1 wt% GO was added. Highlights The TPU/GO composites with static resistance were synthesized by the in-situ polymerization of MDI grafted onto GO tablets. The surface resistance of the TPU/GO was reduced from 1 × 10 12 Ω to 6.67 × 10 9 Ω when 0.25 wt% GO was added, and to 3.33 × 10 7 Ω when 1 wt% GO was added. The antistatic properties of TPU were effectively improved. The tensile strength of TPU/GO reached 63.13 MPa when GO content was 0.5 wt%, which is 23.66 MPa higher than that of pure TPU. The elongation at break is increased by 105.1%. The thermal performance of TPU/GO was improved with the increase of GO content, while both the T g and T d5% of TPU/GO increased by 1–7 °C. At the same temperature, the E′ of TPU/GO with 1 wt% GO addition reached 2353 MPa, which is 505 MPa higher than that (1848 MPa) of pure TPU.