{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T22:26:00Z","timestamp":1783635960969,"version":"3.55.0"},"reference-count":50,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2024,7,5]],"date-time":"2024-07-05T00:00:00Z","timestamp":1720137600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science and Technology Council of Taiwan","award":["NSTC 104-2622-B-002-014-CC2"],"award-info":[{"award-number":["NSTC 104-2622-B-002-014-CC2"]}]},{"name":"National Science and Technology Council of Taiwan","award":["105-2622-B-002-008-CC2"],"award-info":[{"award-number":["105-2622-B-002-008-CC2"]}]},{"name":"National Science and Technology Council of Taiwan","award":["NTU 104-12MZ-18"],"award-info":[{"award-number":["NTU 104-12MZ-18"]}]},{"name":"National Science and Technology Council of Taiwan","award":["105-12MZ-13"],"award-info":[{"award-number":["105-12MZ-13"]}]},{"name":"Chung Hwa Pulp Corporation","award":["NSTC 104-2622-B-002-014-CC2"],"award-info":[{"award-number":["NSTC 104-2622-B-002-014-CC2"]}]},{"name":"Chung Hwa Pulp Corporation","award":["105-2622-B-002-008-CC2"],"award-info":[{"award-number":["105-2622-B-002-008-CC2"]}]},{"name":"Chung Hwa Pulp Corporation","award":["NTU 104-12MZ-18"],"award-info":[{"award-number":["NTU 104-12MZ-18"]}]},{"name":"Chung Hwa Pulp Corporation","award":["105-12MZ-13"],"award-info":[{"award-number":["105-12MZ-13"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Lignins, naturally occurring aromatic polymers with phenylpropane units, are promising bio-based alternatives for petroleum-based products. Resole-type phenol formaldehyde (PF) adhesive is commonly used in wood composites requiring durability and weather-proofness. However, PF adhesive is a petroleum-based product. The objective of this study is to transform the low-reactivity hardwood kraft lignin (KL) as the phenol substitute in the PF adhesive formulation by acidic phenolation. The variations in the molecular weights, chemical structures, and functional groups in lignins were investigated before and after the phenolation. The results indicate that the KL can be cleaved, and phenols are crosslinked onto KL to produce phenolated kraft lignin (PKL) under the suitable phenolation condition, heating 3\/5 (w\/w) of KL\/phenol at 90 \u00b0C for 2 h with 5% H2SO4 as the catalyst. Resole-type PKL-PF adhesives can be directly synthesized after the phenolation in the same reactor. Plywood laminated with this adhesive obtains satisfactory strength and low formaldehyde emission. This not only reduces the usage of petroleum-based phenol but also increases the reactivity and applications for hardwood KL.<\/jats:p>","DOI":"10.3390\/polym16131923","type":"journal-article","created":{"date-parts":[[2024,7,5]],"date-time":"2024-07-05T12:30:59Z","timestamp":1720182659000},"page":"1923","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Phenolation to Improve Hardwood Kraft Lignin for Wood Adhesive Application"],"prefix":"10.3390","volume":"16","author":[{"given":"Li-Yuan","family":"Liu","sequence":"first","affiliation":[{"name":"School of Forestry and Resource Conservation, National Taiwan University, Taipei 106, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wan-Shuan","family":"Chiang","sequence":"additional","affiliation":[{"name":"School of Forestry and Resource Conservation, National Taiwan University, Taipei 106, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hou-min","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4114-6714","authenticated-orcid":false,"given":"Ting-Feng","family":"Yeh","sequence":"additional","affiliation":[{"name":"School of Forestry and Resource Conservation, National Taiwan University, Taipei 106, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"695","DOI":"10.1126\/science.1218930","article-title":"Valorization of biomass: Deriving more value from waste","volume":"337","author":"Tuck","year":"2012","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"396","DOI":"10.1016\/j.reactfunctpolym.2012.05.010","article-title":"Sequential transformation and utilization of natural network polymer \u201cLIGNIN\u201d","volume":"73","author":"Funaoka","year":"2013","journal-title":"React. 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