Cellulose hydrogel skeleton by extrusion 3D printing of solution

Abstract

Abstract Cellulose is the most abundant natural polymer on earth, which has obtained increasing interest in the field of functional materials development for its renewable, high mechanical performance and environmental benign. In this study, the traditional processing method (wet spinning and film production) of cellulose-based materials was applied by using cellulose solution for 3D printing, which can directly build complex 3D patterns. Herein, a natural cellulose is dissolved in an effective mixed aqueous solution of dimethyl sulfoxide (DMSO) and tetrabutylammonium hydroxide (TBAH). The cellulose solution extrusion was controlled by a modified fused deposition modeling (FDM) 3D printer. During the controlled extrusion 3D printing process, the viscous cellulose solution will gelifies and further solidifies into a predetermined 3D pattern at room temperature in air. Subsequently, a cellulose hydrogel skeleton was obtained, when the 3D pattern was solvent-exchanged with deionized water. Finally, the mechanical and swelling performance of the cellulose hydrogel scaffold was improved by a cross-linking agent treatment method. With treatment of the 3D printed scaffolds in 0.8 wt% cross-linking agent solution, the obtained cellulose hydrogel could absorb 28 g/g water, and the compression strength was 96 kPa. This work provided an efficient way to prepare natural cellulose hydrogel by 3D printing under room temperature.