CELF LIGNIN INCORPORATION IN STEREOLITHOGRAPHY RESIN TO ENHANCE MATERIAL PROPERTIES OF 3D PRINTED MATERIAL TO PRODUCE PHOTOACTIVE POLYMERS
Open Access
- Author:
- Arya, Aditi
- Graduate Program:
- Biorenewable Systems
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- August 03, 2021
- Committee Members:
- Jeffrey Catchmark, Professor in Charge/Director of Graduate Studies
Stephen C Chmely, Thesis Advisor/Co-Advisor
Daniel Edward Ciolkosz, Committee Member
Christine Costello, Committee Member
Hilal Ezgi Toraman, Committee Member - Keywords:
- CELF Lignin
SLA
Stereolithography
Petroleum
Lignin Modification
Soy-based Oligomer
Acetylation of Lignin
Environmental Impact Analysis
Resin Formulations
31P NMR
E-factor analysis - Abstract:
- Additive manufacturing is a rapidly growing industry with many opportunities to create finished goods quickly, cheaply, and sustainably. Lignin, a natural aromatic heteropolymer, has potential to be used as a partial replacement for petroleum-derived polymers in the manufacturing of a variety products. Another growing research interest is in the utilization of soy-based oligomer in resins for curing polymers using UV radiation, again replacing petroleum derived chemicals and polymers. Previously, soy-based resins have shown improved mechanical properties when mixed with styrene. In this study cosolvent enhanced lignocellulosic fractionated lignin was chemically modified by acetylation and incorporated into soy-based oligomers to produce photoactive resins for stereolithography. To monitor the methacrylation process, 31P NMR spectroscopy was performed on the resulting resins. 3D printed samples were tested using static tensile testing. Simultaneously, the sustainability of the process was investigated by performing an E-factor analysis of the lignin acetylation process. Resins produced contained 0-10 wt% lignin with diluents, oligomers, and photo-initiators, suitable for use as a 3D printing resins. An increase in the stiffness of the materials that contain modified lignin was observed. This process has a lower e-factor (1.302 g of waste produced per g of product) than a commercial process that uses petrochemical-based materials (<1-5 g of waste produced per g of product). The process developed here demonstrated that the modified lignin incorporated resin demonstrates enhanced stiffness and with efficient use of materials (determined by the E-factor) and increased use of bio-renewable materials.