Synthesis of cellulose nanocrystal armored latex particles for mechanically strong nanocomposite films

Cellulose nanocrystals (CNCs) possess an incredible degree of mechanical strength which makes them interesting candidates in the design of composite materials. In this work, we demonstrate the synthesis of CNC armored latex particles by an emulsion polymerization process. A cationic initiator was used to ensure the adsorption of the negatively charged CNCs onto the latex particle surface. Through careful balance of the cationic/anionic species involved in the adsorption process it is demonstrated that it is possible to achieve stable latexes with high conversion and low particle size. Films were cast from the CNC armored latexes and atomic force microscopy was used to confirm the adsorption to the surface and their even distribution throughout the film. The mechanical properties of the films were measured demonstrating that the addition of CNCs led to a brittle film with extremely high Young's modulus. Blends of the CNC armored particles with a cationically stabilized latex were fabricated in order to demonstrate the potential to produce mechanically strong polymer films for use in conventional coatings applications.