{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:48:43Z","timestamp":1792806523587,"version":"4.5.0"},"reference-count":58,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,8,6]],"date-time":"2025-08-06T00:00:00Z","timestamp":1754438400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Yaound\u00e9 I and the Ministry of Higher Education of Cameroon through the Programme d\u2019Appui \u00e0 la Recherche","id":[{"id":"https:\/\/ror.org\/02xvp8z16","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Lignin used in this work was isolated from sapele (Entandrophragma cylindricum) wood through a hybrid pulping process using soda\/ethanol as pulping liquor and denoted soda-oxyethylated lignin (SOL). SOL was mixed with a polyethylene glycol (PEG)\u2013glycerol mixture (80\/20 v\/v) as liquefying solvent with 98% wt. sulfur acid as catalyst, and the mixture was taken to boil at 140 \u00b0C for 2, 2.5, and 3 h. Three bio-polyols LBP1, LBP2, and LBP3 were obtained, and each of them exhibited a high proportion of -OH groups. Lignin-based polyurethane foams (LBPUFs) were prepared using the bio-polyols obtained with a toluene diisocyanate (TDI) prepolymer by the one-shot method. Gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and carbon-13 nuclear magnetic resonance spectroscopy (13C NMR) were used characterize lignin in order to determine viscosity, yield, and composition and to characterize their structure. The PEG-400\u2013glycerol mixture was found to react with the lignin bio-polyols\u2019 phenolic -OHs. The bio-polyols\u2019 viscosity was found to increase as the liquefaction temperature increased, while simultaneously their molecular weights decreased. All the NCO groups were eliminated from the samples, which had high thermal stability as the liquefaction temperature increased, leading to a decrease in cell size, density, and crystallinity and an improvement in mechanical performance. Based on these properties, especially the presence of some aromatic rings in the bio-polyols, the foams produced can be useful in automotive applications and for floor carpets.<\/jats:p>","DOI":"10.3390\/polym17152156","type":"journal-article","created":{"date-parts":[[2025,8,7]],"date-time":"2025-08-07T08:33:06Z","timestamp":1754555586000},"page":"2156","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Isolation and Characterization of Lignin from Sapele (Entandrophragma cylindricum): Application in Flexible Polyurethane Foam Production"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-4535-1834","authenticated-orcid":false,"given":"Hubert Justin","family":"Nnanga Guissele","sequence":"first","affiliation":[{"name":"Laboratory of Macromolecular Chemistry, Department of Inorganic Chemistry, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8492-1100","authenticated-orcid":false,"given":"Arnaud Maxime Cheumani","family":"Yona","sequence":"additional","affiliation":[{"name":"Laboratory of Macromolecular Chemistry, Department of Inorganic Chemistry, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1482-4954","authenticated-orcid":false,"given":"Armel Edwige","family":"Mewoli","sequence":"additional","affiliation":[{"name":"Laboratory of Engineering Civil and Mechanic, National Advanced School of Engineering, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8183-4888","authenticated-orcid":false,"given":"D\u00e9sir\u00e9","family":"Chimeni-Yomeni","sequence":"additional","affiliation":[{"name":"LABPLAS, 1951 Rue Nobel, Sainte-Julie, QC J3E 1Z6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucioni Fabien","family":"Tsague","sequence":"additional","affiliation":[{"name":"Laboratory of Macromolecular Chemistry, Department of Inorganic Chemistry, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tatiane Marina","family":"Abo","sequence":"additional","affiliation":[{"name":"Laboratory of Macromolecular Chemistry, Department of Inorganic Chemistry, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3246-4048","authenticated-orcid":false,"given":"Jean-Bosco","family":"Saha-Tchinda","sequence":"additional","affiliation":[{"name":"Laboratory of Macromolecular Chemistry, Department of Inorganic Chemistry, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maurice Kor","family":"Ndikontar","sequence":"additional","affiliation":[{"name":"Laboratory of Macromolecular Chemistry, Department of Inorganic Chemistry, University of Yaound\u00e9 I, Yaound\u00e9 P.O. Box 812, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9749-7185","authenticated-orcid":false,"given":"Antonio","family":"Pizzi","sequence":"additional","affiliation":[{"name":"ENSTIB-LERMAB, University of Lorraine, 27 Rue Philippe Seguin, P.O. Box 21042, 88051 Epinal, Cedex 9, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ragauskas, A.J., Beckham, G.T., Biddy, M.J., Chandra, R., Chen, F., Davis, M.F., Davison, B.H., Dixon, R.A., Gilna, P.K., and Langan, M.P. (2014). Lignin valorization: Improving lignin processing in the biorefinery. Science, 344.","DOI":"10.1126\/science.1246843"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1515\/hfsg.1986.40.6.353","article-title":"Engineering plastics from lignin-XIII. 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