Diglycidylether of iso-eugenol: a suitable lignin-derived synthon for epoxy thermoset applications

Abstract

International audienceA novel lignin-based synthon, diglycidylether of iso-eugenol (DGE-isoEu) is used as a prepolymer for the preparation of thermosetting resins. DGE-isoEu is synthesized in a two-step procedure with a satisfactory yield from bio-based iso-eugenol (isoEu, 2-methoxy-4-(1-propenyl)phenol) catalytically fragmented from lignin in an organosolv process. DGE-isoEu was fully characterized by NMR, MS and FTIR. Curing of the DGE-isoEu monomer has then been investigated in the presence of several carboxylic acid derivatives hardeners. The thermal and mechanical properties of each material were recorded showing, in particular, a high T-g and instantaneous modulus values in the range of 78-120 degrees C and 4.6-5.5 GPa, respectively. The lignin derived new materials give very attractive thermo-mechanical properties comparable to that of common BPA-containing epoxy resins

New Eco-Friendly Synthesized Thermosets from Isoeugenol-Based Epoxy Resins

“…HHPA reacts with BioIgenox at a lower temperature than CA (see Figure 2), as it was previously reported by our team in the case of GEEpiE [21,22]. Not surprisingly, no endothermic fusion peak is observed at 100 • C on the DSC thermogram.…”

“…The reaction of isoeugenol with epichlorohydrin leads, as expected, to glycidyl ether isoeugenol [21]. Two by-products, DiEP1 and DiEP2, are also formed according to the reaction mechanism shown in Scheme 5.…”

“…Within this context, our research team has recently described both the synthesis of an epoxy monomer derived from isoeugenol, named as GlycidylEther Epoxy isoeugenol (GEEpiE) [21], and its curing with camphoric anhydride [22]. Behaviours of the resulting thermoset are consistent with its use as a bio-based epoxy matrix for structural composites.…”

“…This way induces a variability of the resulting materials properties since the content of lignin in different types of biomass resources varies strongly. An alternative approach consists of lignin fragmentation [10][11][12] leading to a wide range of building blocks, such as vanillin [13][14][15], rosin [16], eugenol [17][18][19][20] and isoeugenol [21,22], which are then epoxidized.Within this context, our research team has recently described both the synthesis of an epoxy monomer derived from isoeugenol, named as GlycidylEther Epoxy isoeugenol (GEEpiE) [21], and its curing with camphoric anhydride [22]. Behaviours of the resulting thermoset are consistent with its use as a bio-based epoxy matrix for structural composites.…”

Synthesis and Characterization of Epoxy Thermosetting Polymers from Glycidylated Organosolv Lignin and Bisphenol A

“…Vanillin‐based epoxy thermosets were described in detail by Caillol and co‐workers . Recently, epoxy thermosets from glycidylated iso‐eugenol were presented . In contrast, the macromolecular approach, i.e ., the use of modified lignin as reactive monomer in epoxy thermosets, is more challenging due to the heterogenic structure of lignin and structural differences emerging through pulping procedures (Kraft, Organosolv, sulfite, pyrolysis, steam explosion,…).…”