(167aq) High performance lignin-based coatings

Petroleum-based aromatic compounds are commonly used in industries to produce rigid and thermally stable materials as a result of the few green alternatives able to provide the same chemical and mechanical properties. Lignin represents the most promising source of aromatic natural polymers deriving from wood biomass. However, its heterogenous structure makes it commonly an inconsistent and low-reactivity precursor. Therefore, in this project, fractionation of softwood LignoBoost^TM Kraft lignin is performed using microwave-assisted technique in order to produce narrow-dispersity and low molecular weight oligomers. Once lignin fractions are obtained, hydroxyl groups are targeted for functionalization through microwave-assisted allylation. Spectroscopy analyses (FT-IR, NMR) allow to provide a detailed description of the technical lignin structures before and after the reaction. Moreover, morphological properties are investigated using Scanning Electro Microscopy. Allylated lignin is subsequently crosslinked through thermally induced thiol-ene chemistry in order to produce fully bio-based thermosets. Afterwards their thermal and mechanical properties are analyzed using micro indentation hardness testing.