title: Solvent- and Halogen-Free Modification of Biobased Polyphenols to Introduce Vinyl Groups: Versatile Aromatic Building Blocks for Polymer Synthesis.
abstract: Various biobased polyphenols (lignins and condensed tannins) were derivatized with vinyl ethylene carbonate, a functional cyclic carbonate, to obtain multifunctional aromatic polymers bearing vinyl groups. The reaction was optimized on a condensed tannin and soda lignin. In both cases, full conversion of the phenol groups was achieved in only 1 h at 150 °C without solvent and with K2CO3as a cheap and safe catalyst. This reaction was later applied to other condensed tannins and technical lignins (Kraft and organosolv), showing only little dependence on the chemical structure of the polyphenols. The obtained derivatives were thoroughly characterized by1H and31P NMR spectroscopy, FTIR spectroscopy, and size-exclusion chromatography. The developed method was compared with previously published protocols for the introduction of vinyl groups on lignin, and shows promising advances toward the modification of biobased polyphenols according to green chemistry principles. The obtained macromolecules show great potential as highly versatile biobased aromatic building blocks for the synthesis of polymers through, for example, radical, metathesis, or thiol-ene reactions.
authors.affiliation: BioTeam/ICPEES-ECPM, UMR 7515, Université de Strasbourg, 25 rue Becquerel, 67087, Strasbourg Cedex 2, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Duval
authors.affiliation: BioTeam/ICPEES-ECPM, UMR 7515, Université de Strasbourg, 25 rue Becquerel, 67087, Strasbourg Cedex 2, France.
authors.forename: Luc
authors.identifier: 0000-0002-2797-226X
authors.initials: L
authors.lastname: Avérous
mesh_terms: D002850:Chromatography, Gel; D006219:Halogens / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D059808:Polyphenols / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D006219:Halogens; D011108:Polymers; D059808:Polyphenols; D012997:Solvents
keywords: cyclic carbonates; lignin; polyphenols; solvent-free; vinyl groups