Fully Bio‐Based Epoxy Thermoset Based on Epoxidized Linseed Oil and Tannic Acid

• Published in: Macromolecular materials and engineering Vol. 307; no. 12
• Main Authors: Reinhardt, Nikita, Breitsameter, Jonas M., Drechsler, Klaus, Rieger, Bernhard
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01.12.2022
• Subjects: bio‐based materials; Curing agents; epoxidized linseed oil; epoxidized vegetable oils; Epoxy resins; epoxy thermoset; Flexural strength; Glass transition temperature; Linseed oil; Material properties; Modulus of rupture in bending; Stiffness; Tannic acid; Vegetable oils
• ISSN: 1438-7492; 1439-2054
• DOI: 10.1002/mame.202200455

Increasing demand for bio‐based epoxy thermoset alternatives has risen in the last few years. Epoxidized vegetable oils (EVO) have attracted significant attention due to their bio‐based, unharmful nature and high availability. This study proposes a fully bio‐based epoxy thermoset based on epoxidized linseed oil (ELO) and tannic acid (TA). TA allows, with its high degree of functionality and aromatic structure as a curing agent for ELO, to create a fully bio‐based polymer network with a high glass transition temperature (Tg), high stiffness, and high strength. A maximum Tg of 146 °C, a flexural modulus of 2986 MPa, and flexural strength of 72 MPa are obtained. The strong material properties of the TA/ELO thermoset expose its potential as a bio‐based substitute for petrochemical‐based epoxy resins for high‐performance applications. By using epoxidized linseed oil and tannic acid to produce a bio‐based thermoset, this work pursues the approach of replacing hazardous and petrochemical‐derived materials with nontoxic bio‐based materials while preserving the efficacy of function. Thus, good thermal‐ and mechanical properties such as a flexural modulus of 2986 MPa, Tg of 147 °C, or flexural strength of 72 MPa could be obtained.