Influence of cellulose nanocrystals concentration and ionic strength on the elaboration of cellulose nanocrystals-xyloglucan multilayered thin films

International audienceThe effect of the variation of CNC concentration on the growth pattern of CNC-XG films is investigated. We found that a transition in the growth slope occurs at a CNC concentration of roughly 3-4 g L-1. A close effect can be obtained by the increase of the ionic strength of the CNC suspensions, suggesting that electrostatic interactions are involved. Static light scattering investigation of CNC dispersions at increasing concentrations demonstrated that the particle-particle interactions change as the CNC concentration increases. Neutron Reflectivity (NR) was used to probe the internal structure of the films. The increase of the CNC concentration as well as the increase of the ionic strength in the CNC suspension were found to induce a densification of the adsorbed CNC layers, even though the mechanisms are not strictly identical in both cases. Small changes in these parameters provide a straightforward way of controlling the architecture of CNC-based multilayered thin films and, as a result, their functional properties