Preparation of amino-functionalized graphene oxide by Hoffman rearrangement and its performances on polyacrylate coating latex

• Prepare amino-functionalized graphene oxide(NGO) by Hoffman rearrangement successfully.
• NGO had good dispersibility in polyacrylate latex and film above pH 6 by electrostatic force.
• NGO improved the mechanical and thermal properties of the polyacrylate/NGO composite at a stable disperse state.

Amino-functionalized graphene oxide (NGO) was prepared by Hoffman rearrangement where carboxyl group was replaced directly by amino group instead of using long-chain containing amino group. The chemical structure of NGO was studied by FT-IR, UV–vis, Raman, XPS and TGA. NGO was incorporated into polyacrylate latex (PA) by blending to prepare PA/NGO composite. The dispersibility of NGO in PA latex was significantly influenced by pH values. When the pH value was higher than 6, NGO uniformly dispersed in PA. The mechanical properties of the PA/NGO film were relayed on the pH. The break strength of the film was increased from ∼2 MPa to ∼5 MPa but the elongation at break decreased from 475% to 258% compared with those of PA film. The glass transition temperature (Tg) of PA/NGO film increased by 3.48 °C. For the sake of comparison, the mechanical properties and Tg of a similar composite but with bare graphene oxide (PA/GO) are presented.