Exploring Allylation and Claisen Rearrangement as a Novel Chemical Modification of Lignin

Zoia, Luca; Salanti, Anika; Frigerio, Paola; Orlandi, Marco

doi:10.15376/biores.9.4.6540-6561

Cited by 32 publications

(44 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Anyway, due to the similar SEC curve, the amount of allylation must have been rather low. Interestingly, if the allylation reactions [17][18][19][20]. The M n values ranged between 1900 and 2700 g/mol.…”

Section: Optimization Of the Allylation Of Ol Using Different Basesmentioning

confidence: 99%

“…1 With a content of [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] wt%, lignin is a main component of biomass such as wood and annual plants. The total lignin resources on earth are estimated to be 300 billion tons, with a natural production of 20 billion tons per year.…”

Section: Introductionmentioning

confidence: 99%

“…19 However, the used reagents are toxic and not environmentally benign. Moreover, stoichiometric amounts of a base are required.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Sustainable allylation of organosolv lignin with diallyl carbonate and detailed structural characterization of modified lignin

Over

Meier

2016

Green Chem.

View full text Add to dashboard Cite

The allylation of European beech wood organosolv lignin (OL) with diallyl carbonate (DAC) in the presence of base catalysts is shown to be an efficient, non-toxic, and sustainable modification technique. Comparative studies of different bases and temperatures were performed to optimize the solvent-free allylation of OL. Up to 90% of the aromatic and aliphatic hydroxyl groups in OL were converted to the respective allyl ethers or allyl carbonates using tetrabutylammonium bromide (TBAB) as recyclable base. The demonstrated strategy allows the introduction of functional groups into the structure of lignin, which will enable further modification. Detailed structural analytics by 31 P, 1 H, and 13 C NMR, as well as IR spectroscopy and detailed mass analysis using SEC-ESI-MS verified the functionalization and delivered insights into the structure of lignin.

show abstract

Section: Optimization Of the Allylation Of Ol Using Different Basesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sustainable allylation of organosolv lignin with diallyl carbonate and detailed structural characterization of modified lignin

Over

Meier

2016

Green Chem.

View full text Add to dashboard Cite

show abstract

“…[13][14][15][16][17][18][19][20] Other functionalities allowing furtherp olymerization have been introduced in lignins or tannins, such as furan and maleimide, [21][22][23] alkyne, [24] epoxy, [25][26][27][28][29] cyclic carbonate, [30] or carboxyl groups. Different kinds of vinyl groups have been introduced on lignin or lignin model compounds, such as allyl, [34][35][36][37] ethylvinylether, [35] styryl, [35,38] acrylic, [39] or methacrylic groups. Different kinds of vinyl groups have been introduced on lignin or lignin model compounds, such as allyl, [34][35][36][37] ethylvinylether, [35] styryl, [35,38] acrylic, [39] or methacrylic groups.…”

Section: Introductionmentioning

confidence: 99%

“…Different kinds of vinyl groups have been introduced on lignin or lignin model compounds, such as allyl, [34][35][36][37] ethylvinylether, [35] styryl, [35,38] acrylic, [39] or methacrylic groups. [35][36][37][38][39][40] Recently,O ver and Meier developed am ore sustainable protocol to allylate lignin with diallylcarbonate. [35][36][37][38][39][40] Recently,O ver and Meier developed am ore sustainable protocol to allylate lignin with diallylcarbonate.…”

Section: Introductionmentioning

confidence: 99%

Solvent‐ and Halogen‐Free Modification of Biobased Polyphenols to Introduce Vinyl Groups: Versatile Aromatic Building Blocks for Polymer Synthesis

Duval

Avérous

2017

ChemSusChem

View full text Add to dashboard Cite

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 K CO as 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 by H and P 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.

show abstract

Microwave‐assisted fractionation and functionalization of technical lignin toward thermoset resins

Truncali,

Ribca,

Yao

et al. 2023

J of Applied Polymer Sci

View full text Add to dashboard Cite

Lignin is the most abundant aromatic biopolymer, with a potential to serve as a building block of rigid and thermally stable bio‐based materials. However, it is still underutilized because of the heterogeneous and not fully understood chemical structure. Here, technical softwood Kraft lignin is refined in to narrow‐dispersity and relatively low molar mass fractions by microwave‐assisted processing, followed by microwave‐assisted allylation and further application in lignin‐based thermosets. This microwave processing is carried out under non‐catalyzed conditions using a low boiling point solvent and elevated pressure. The properties of the retrieved fractions are investigated by 31P‐NMR, heteronuclear single quantum coherence spectroscopy‐NMR, SEC, differential scanning calorimetry, and thermogravimetric analysis. The extraction yield of the selected lignin fraction is around 25%, with the number‐average molar mass (Mn), weight‐average molar mass (Mw), and dispersity (Đ) significantly reduced. The chemically modified lignin is characterized by 31P NMR and FTIR, which provides evidence of the introduction of the allyl moieties. The analyses demonstrate that 90 ± 3% of the hydroxyl groups in fractionated lignin are successfully allylated. Subsequently, the allylated lignin is cross‐linked through thermally induced thiol‐ene chemistry to produce lignin‐based thermosets. The final thermosets exhibit a storage modulus of 4050 ± 60 MPa and a Tg of 105 ± 5°C.

show abstract

Exploring Allylation and Claisen Rearrangement as a Novel Chemical Modification of Lignin

Cited by 32 publications

References 11 publications

Sustainable allylation of organosolv lignin with diallyl carbonate and detailed structural characterization of modified lignin

Sustainable allylation of organosolv lignin with diallyl carbonate and detailed structural characterization of modified lignin

Solvent‐ and Halogen‐Free Modification of Biobased Polyphenols to Introduce Vinyl Groups: Versatile Aromatic Building Blocks for Polymer Synthesis

Microwave‐assisted fractionation and functionalization of technical lignin toward thermoset resins

Contact Info

Product

Resources

About