Rheological behavior of hybrid suspensions of chitin nanorods and siloxane oligomers

Abstract

Polysaccharide nanocrystals (chitin, cellulose) extracted from biomass are increasingly considered as templates to produce hierarchical anisotropic features in inorganic phases. The organization of nanostructured solids obtained after sol-gel processing results from the complex combination of van der Waals and electrostatic interactions as well as excluded volume effects. Here, we investigate the rheological behavior of colloidal suspensions of chitin nanorods and siloxane oligomers in ethanol. The effects of solvothermal treatments and hydrophobized oligomers were also studied to decipher the respective role of inter-particle colloidal interactions. We demonstrate that interactions between chitin nanorods are strongly affected by the presence of siloxane oligomers. In agreement with previous works, the rheological data confirm the association of the small colloidal siloxane oligomers with the chitin surface. This knowledge is key information to further control the localization of functions in the resulting materials (nanocomposites, catalysts).