Bacterial cellulose nanofibers modification with 3-(trimethoxysilyl)propyl methacrylate as a crosslinking and reinforcing agent for 3D printable UV-curable inks

Cellulose nanofibers (CNF) produced by bacterial were functionalized along the surface with 3-(trimethoxysilyl)propyl methacrylate (TMSPM). The chemical and crystalline structure of the material was confirmed with NMR, FTIR, EDX and XRD methods. Modified CNF were used as a crosslinker and reinforcer for polymerizable deep eutectic solvent (DES) based on acrylic acid and choline chloride. Dispersions of modified nanofibers in DES were applied as UV-curable ink for 3D printing. It was shown that shielding of -OH groups of the cellulose surface with TMSPM increased the quality of 3D printed filaments due to reduced CNF agglomeration. At the same time, surface methacrylic groups copolymerize with acrylic acid forming crosslinked ion gel. Elastic moduli of the prepared ion gels were identical to those of gels based on unmodified CNF and crosslinked with N,N'-methylenebisacrylamide. However, strength and the ultimate elongation of the material prepared in this work were 1.05 ± 0.08 MPa at 2700% that is significantly higher than those of the material prepared with unmodified CNF. Graphical Abstract