Considerations about highly crystalline cellulose microfiber additive from Eucalyptus grandis for 3D-printing acrylonitrile butadiene styrene filament

The current work aimed to produce acrylonitrile butadiene styrene (ABS) filament with cellulose microfibers additive for three-dimensional (3D)-printing and perform initial mechanical characterizations. 3D printing is a Fourth Industrial Revolution enabling technology aimed at smart production process. Cellulose is an organic molecule extremely common in nature with potential application as materials reinforcement. Highly crystalline cellulose microfibers were extracted from certified Eucalyptus grandis wood. E. grandis is a species native to Australia, but widely used in reforestation initiatives on a global scale. Cellulose microfiber was inserted at 0.5% in weight into commercial ABS to produce filaments for 3D printing. After the production of pure ABS and ABS with microcellulose filaments, specimens were printed using fused deposition modeling for traction, flexion, and impact tests, in addition to measuring the melt flow index. The results between the two materials were compared, revealing that most of the mechanical properties were similar within the limits of experimental errors, but the strain at break in the traction test was improved in microfibers composite, in addition to an improvement in the elastic modulus and stress at break in flexion test. On melt flow index measurement, both materials were found to be considerably more fluid than the polymer from commercial producer sources. This is an indication that the ABS degraded throughout the process, losing molar mass. However, our work demonstrated that it is possible to add highly crystalline cellulose microfibers to ABS to form filaments for 3D printing.