Session: 04-23-01: Functional Soft Composites - Design, Mechanics, and Manufacturing

Paper Number: 144474

144474 - Digital Light Processing (Dlp) 3d Printing of High Particle Loading Polymer Composites for Sustainable Additive Manufacturing 

The rapid development of synthetic polymers has brought significant benefits and challenges, including environmental pollution, over the last century. In recent decades, additive manufacturing (AM) of plastics has emerged as a promising technique for efficiently constructing complex structures, with its applications expanding rapidly. Consequently, the amount of plastic waste from 3D printing techniques is also increasing significantly. Utilizing plastic waste as feedstock for 3D printing offers a sustainable way to lessen the environmental impact of plastic waste and reduce the overall cost of 3D printing. This method has been explored for extrusion-based AM techniques, such as fused filament fabrication (FFF), by using recycled plastic as filament. In our study, we utilized polymer powder derived from cryogenically milled common plastic wastes, including HDPE, LDPE, PP, PET, and PS, as feedstock for DLP 3D printing. The incorporation of fine polymer powders into DLP ink affects the curing process, as the scattering and blocking of UV light by the particles in the resin can negatively impact the properties of the printed objects. To overcome this challenge, we employed a two-stage curing process. Initially, samples undergo UV curing during the printing process, followed by thermal curing. Thermal curing aids in enhancing the mechanical properties of the printed objects by completing the polymerization and crosslinking processes, which may remain incomplete due to the solid particles in the ink blocking the UV light. We conducted a systematic study on the impact of the powder and curing process on various aspects such as printability, mechanical properties, flow behavior, and printing precision. By employing this technique, we were able to fabricate polymeric composites via DLP 3D printing with high loadings (up to 35 wt.%), representing a sustainable manufacturing practice. Importantly, the overall properties of the 3D printed objects remained largely unaffected.

Presenting Author: Farzad Gholami Georgia Institute of Technology

Presenting Author Biography: I'm Farzad Gholami, a second-year Ph.D. student in the mechanical engineering department at Georgia Tech, where I'm exploring the realm of additive manufacturing of soft materials. My journey into this field is built upon a foundation in materials science and engineering, with a further specialization in polymer science. This background has prepared me to delve into the complexities and opportunities that soft materials present in modern manufacturing processes.

Authors:

Farzad Gholami Georgia Institute of Technology
Nandita Gallacher Georgia Institute of Technology
Marcus Fratarcangeli Georgia Institute of Technology
Mingzhe Li Georgia Institute of Technology
Jerry Qi Georgia Institute of Technology