Sustainable epoxy resin coating formulations based on epoxidised lignin

 
Sustainable epoxy resin coating formulations based on epoxidized lignin Mihaela Tanase-Opedal1, Leesa Jane Klau2, Line Omtvedt3, Francesca di Bartolomeo4 1PFI AS, Høgskoleringen 6B, NO-7491 Trondheim, Norge 2Sintef Industry, Department of Process Technology, Oslo, Norge 3JOTUN A/S, Hystadveien 167, 3209 Sandefjord, Norge 4Sintef Industry, Department of Biotechnology and Nanomedicine, Trondheim, Norge Abstract Epoxy resins based on diglycidyl ether of bishenol A (DGEBA) are widely applied in various fields due to the high corrosion resistance properties and is an important constituent of anticorrosive coatings used for steel protection. However, Bisphenol A is derived from fossil resources possessing a great concern for the environment and human health. Lignin, due to the high industrial availability, aromatic structure and functionality can be incorporated in epoxy resins coating formulations to replace bisphenol A. The aim of this study is to produce a sustainable and bio-based lignin resin for anticorrosive coatings. In our study, in-house produced organosolv lignin with low molecular weight, high reactivity and functionality were first epoxidized and thereafter cured with three different commercial curing agents. Clear coats were prepared and cured on steel panels varying the content of epoxidized lignin resin. The formation of epoxide rings in the lignin structure was confirmed by Fourier transform infrared spectroscopy (FTIR) and NMR. Thermal properties and mass loss were analyzed by thermogravimetric analysis and differential scanning calorimetry (TGA/DSC). The preliminary results suggests that epoxidized organosolv lignin has the potential to replace bisphenol A in epoxy resin coatings formulations.