{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T03:19:03Z","timestamp":1773285543035,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,3,4]],"date-time":"2022-03-04T00:00:00Z","timestamp":1646352000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["Project N. \u00ba 21874"],"award-info":[{"award-number":["Project N. \u00ba 21874"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Oxyalkylation with propylene carbonate (PC) is a safe process to convert lignin into a reactive liquid polyol to be used in polyurethane formulations. In this study, the effect of operating conditions of oxyalkylation (temperature, time and quantify of PC) on the quality of lignin-based polyol in terms hydroxyl number (IOH) and viscosity was studied. Full factorial modeling and response surface methodology (RSM) were applied to study the effect and interaction of process variables on the IOH and viscosity of lignin-based polyols. The results revealed that the IOH is highly affected by the reaction time, while the viscosity is affected by the amount of PC. Validation experiments confirmed the model is reliable. Furthermore, RSM optimization allowed to reduce the amount of PC by about 50% and to increase the lignin content in the polyol from 12.5% to 25% (w\/w) depending on the temperature and time of the process and also on the purpose of the polyol produced (i.e., application in rigid foams or adhesives).<\/jats:p>","DOI":"10.3390\/ma15051925","type":"journal-article","created":{"date-parts":[[2022,3,6]],"date-time":"2022-03-06T20:38:16Z","timestamp":1646599096000},"page":"1925","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Oxyalkylation of Lignoboost\u2122 Kraft Lignin with Propylene Carbonate: Design of Experiments towards Synthesis Optimization"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3017-8462","authenticated-orcid":false,"given":"Fernanda Rosa","family":"Vieira","sequence":"first","affiliation":[{"name":"Department of Chemistry, CICECO-Institute of Materials, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6462-8679","authenticated-orcid":false,"given":"Ana","family":"Barros-Timmons","sequence":"additional","affiliation":[{"name":"Department of Chemistry, CICECO-Institute of Materials, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6304-5105","authenticated-orcid":false,"given":"Dmitry Victorovitch","family":"Evtuguin","sequence":"additional","affiliation":[{"name":"Department of Chemistry, CICECO-Institute of Materials, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Paula C. O. R.","family":"Pinto","sequence":"additional","affiliation":[{"name":"RAIZ, Forest and Paper Research Institute, Quinta de S. Francisco, 3801-501 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1002\/jctb.5149","article-title":"New approaches to producing polyols from biomass","volume":"92","year":"2017","journal-title":"J. Chem. Technol. Biotechnol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Gama, N.V., Ferreira, A., and Barros-Timmons, A. (2018). Polyurethane foams: Past, present, and future. Materials, 11.","DOI":"10.3390\/ma11101841"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2000033","DOI":"10.1002\/ejlt.202000033","article-title":"Bio-Based, Self-Condensed Polyols","volume":"122","author":"Ionescu","year":"2020","journal-title":"Eur. J. Lipid Sci. 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