Wood-derived cellulose fibrils at the nanoscale are promising for reinforcement and controlled modification of polymer matrices. It is feasible that the mechanical properties of polymers and their functionality can be designed by compounding properly processed and refined cellulose fibrils. In order to induce an optimal compounding of the fibrils with different (bio)polymers, good fibril/matric embedding is required. Therefore, cellulose fibrils must be modified approximately to match the hydrophilic or hydropho-bic nature of the polymer matrix. This presentation provided insights into our research regarding the chemical tailoring of cellulose fibrils for applications in wood adhesion (e.g., one-component polyurethane adhesives, [lc-PUR]) as well as for the compounding with (bio)polymers (e.g., polylactic acid, polypropylene, low-density polyethylene) for (bio)fiber production. Suspensions of cellulose fibrils resulting from the homogenization of bleached wheat straw pulp were chemical surface-treated using mainly esterification and etherification reactions (e.g., silylation, acety-lation, allylhydroxpropylation, etc.). The resulting dry chemical modified cellulose fibrils were characterized by spectroscopical (NMR, FTIR, XPS) and morphological (SEM-EDX, TEM) methods. Dry silylated fibrils could be dispersed successfully in the polyol component used for the preparation of lc-PUR. The properties (morphology, rheology, gluing, thermo mechanics) of silylated cellulose fibrils based lc-PUR adhesives were discussed and compared with adhesives prepared with un-derivatized fibrils (derived from aqueous fibril suspension).
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