Emulsion templating has emerged as an effective approach to prepare polymer-based foams. This study reports a thermosetting nanocomposite foam prepared by nanocellulose stabilized Pickering emulsion templating. The Pickering emulsion used as templates for the polymeric foams production was obtained by mechanically mixing cellulose nanocrystals (CNCs) water suspensions with the selected oil mixtures comprised of acrylated epoxidized soybean oil (AESO), 3-aminopropyltriethoxysilane (APTS), and benzoyl peroxide (BPO). The effects of the oil to water weight ratio (1:1 to 1:3) and the concentration of CNCs (1.0⁻3.0 wt %) on the stability of the emulsion were studied. Emulsions were characterized according to the emulsion stability index, droplet size, and droplet distribution. The emulsion prepared under the condition of oil to water ratio 1:1 and concentration of CNCs at 2.0 wt % showed good stability during the two-week storage period. Nanocomposite foams were formed by heating the Pickering emulsion at 90 °C for 60 min. Scanning electron microscopy (SEM) images show that the foam has a microporous structure with a non-uniform cell size that varied from 0.3 to 380 μm. The CNCs stabilized Pickering emulsion provides a versatile approach to prepare innovative functional bio-based materials.
Keywords: AESO; Pickering emulsion; cellulose nanocrystals; nanocomposite foam.