Water vapor barrier coating based on nanocellulose crystals stabilized AESO oil-in-water Pickering emulsion

Nanocellulose crystals (NCC) are efficient bio-particles in preparing Pickering emulsion with sustainable merits. In this study, a thermally curable coating emulsion was developed by stabilizing sustainable acrylate epoxidized soybean oil (AESO) in water using pristine NCC alone. A stable AESO aqueous emulsion was obtained by adjusting the AESO fraction to 10% and the concentration of NCC to 1.0 wt%. Fluorescence microscopy and conductivity measurement confirmed the emulsion inversed from oil-in-water to water-in-oil as AESO fraction increasing. Pickering emulsion of NCC concentrations ranging from 0.5 wt% to 3.0 wt% exhibited different droplets microstructure and rheological behavior. Increasing the concentration of NCC enhanced the stability of the corresponding emulsion, including an increase in viscosity and deformation recovery ability. The stability of the emulsion was correlative with the concentration of NCC suspensions, and the dynamic viscoelastic study provided useful guidance for identifying the fine difference between emulsions with respect to NCC concentration. Implementing of the AESO emulsion as a reactive coating on paper enhanced the paper water barrier and tensile strength due to the curing of AESO. This novel NCC stabilized AESO emulsion is surfactant-free in preparation and has a flexible application on paper as a reactive coating for enhanced barrier performances. • Sustainable oil in water emulsions is produced by nanocellulose crystals stabilized epoxy soybean oil acrylate. • The droplet size of emulsions decreases with increasing NCC concentration. • Rheological behavior of emulsions and stability of emulsions are closely related to NCC concentration. • Enhanced protection of emulsion droplets at higher NCC concentrations • The emulsion coating on paper enhanced the mechanical and water vapor barrier property.