Development of bio-based 3D printing filaments from PLA and chemically modified Kraft lignin

• Grant number: 21/12726-2
• Support type: Research Grants - Innovative Research in Small Business - PIPE
• Duration: February 01, 2022 - January 31, 2024
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal researcher: Lara Tavares dos Santos
• Grantee: Lara Tavares dos Santos
• Company: Entropic Solutions - Tecnologias a Partir de Biomassa Ltda
• CNAE: Fabricação de artefatos de material plástico não especificados anteriormente
• City: São Caetano do Sul
• Associated research grant: 20/00876-7 - Development of sustainable filaments for 3D Printing from PLA and kraft lignin, AP.PIPE
• Associated scholarship(s): 22/00365-8 - Development of renewable filaments for 3D printing from PLA e chemically modified kraft lignin, BP.PIPE

Abstract

During the first part of this project, the technical feasibility (proof of concept) of obtaining printable filaments from poly(lactic acid) (PLA) and Kraft lignin, previously modified by esterification reaction with acetic anhydride or with acid lactic, was demonstrated. Alongside the experimental work, several interviews were conducted with professionals in the 3D printing market, professionals from the chemical industry and academics from polymer science field; aiming to identify technological needs and fit the project to the company's business model. The results of phase 1 demonstrated the possibility of obtaining filaments with up to 40% modified lignin in PLA. Despite being printable, these filaments present a critical improvement point, which is the decrease in brittleness. Furthermore, the rheological behavior of these filaments and their relationship with 3D printing behavior has not yet been fully elucidated. Thus, phase 2 of this project proposes an experimental work on two fronts, which are: (1) optimization of lignin modification reactions and adaptation of the process to a pilot reactor and (2) optimization of the properties and characterization of filaments for 3D printing developed in phase 1. At the end of this phase, we expect to obtain blends from PLA/chemically modified-lignin for 3D printing that yields printed parts with superior mechanical properties at a competitive cost. In addition, these blends will be characterized in terms of their biodegradability, thus enabling their use in other applications, after slight changes in their composition. The results obtained in this project will encourage the development of an innovative product, with environmental appeal, without competitors in the national market and which has already attracted interest from potential customers and business partners. (AU)