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Registro Completo |
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Biblioteca(s): |
Embrapa Florestas. |
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Data corrente: |
07/08/2025 |
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Data da última atualização: |
19/08/2025 |
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Tipo da produção científica: |
Artigo em Periódico Indexado |
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Autoria: |
LOMONACO, D.; AVELINO, F.; MATOS, M.; LOURENCON, T.; MAGALHAES, W. L. E. |
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Afiliação: |
DIEGO LOMONACO, UNIVERSIDADE FEDERAL DO CEARA; FRANCISCO AVELINO, UNIVERSIDADE FEDERAL DO CEARA; MAURÍCIO MATOS, SENAI; TAINISE LOURENCON, AALTO UNIVERSITY; WASHINGTON LUIZ ESTEVES MAGALHAES, CNPF. |
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Título: |
Innovative application of dynamic mechanical analysis for accurate glass transition determination in technical lignins. |
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Ano de publicação: |
2025 |
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Fonte/Imprenta: |
Journal of Polymer Research, v. 32, n. 8, 2025. |
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ISSN: |
1022-9760 |
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DOI: |
https://doi.org/10.1007/s10965-025-04485-y |
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Idioma: |
Inglês |
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Conteúdo: |
Sustainable chemistry is driving attention to the use of lignocellulosic materials. Among those, lignin stands out as an alternative for phenolic compounds. Lignin is a powdered amorphous biopolymer, which glass transition temperature (Tg) is commonly assessed by differential scanning calorimetry (DSC). As Tg is related to molecular relaxation of the polymer structure, it varies according to the plant species, isolation method, etc., and many authors report the difficulty in clearly assessing lignin's Tg by DSC. Another technique which is sensitive and precise in determining relaxation processes is Dynamic Mechanical Analysis (DMA) but is usually employed to self-supporting samples. Here, we assessed the Tg of different powdered samples of technical Eucalyptus lignins by DMA and compared it with DSC and chromatographic analysis. The nature of Eucalyptus lignins (MWL, Kraft, Pyrolytic, and Organosolv lignins), heating rate (3, 5, and 10 K min-1), and humidity were evaluated. The results revealed well-defined relaxation processes occurring at temperatures similar to the baseline shift observed in the DSC thermogram, which is typically considered as the Tg. Furthermore, it was found that some factors such as heating rate and humidity did not significantly affect the Tg values obtained by DMA, but it exerts a considerable influence on those obtained by DSC. The main conclusion is that DMA is a precise tool for assessing the Tg of lignin and therefore should be considered by researchers as a new instrument for lignin characterization. MenosSustainable chemistry is driving attention to the use of lignocellulosic materials. Among those, lignin stands out as an alternative for phenolic compounds. Lignin is a powdered amorphous biopolymer, which glass transition temperature (Tg) is commonly assessed by differential scanning calorimetry (DSC). As Tg is related to molecular relaxation of the polymer structure, it varies according to the plant species, isolation method, etc., and many authors report the difficulty in clearly assessing lignin's Tg by DSC. Another technique which is sensitive and precise in determining relaxation processes is Dynamic Mechanical Analysis (DMA) but is usually employed to self-supporting samples. Here, we assessed the Tg of different powdered samples of technical Eucalyptus lignins by DMA and compared it with DSC and chromatographic analysis. The nature of Eucalyptus lignins (MWL, Kraft, Pyrolytic, and Organosolv lignins), heating rate (3, 5, and 10 K min-1), and humidity were evaluated. The results revealed well-defined relaxation processes occurring at temperatures similar to the baseline shift observed in the DSC thermogram, which is typically considered as the Tg. Furthermore, it was found that some factors such as heating rate and humidity did not significantly affect the Tg values obtained by DMA, but it exerts a considerable influence on those obtained by DSC. The main conclusion is that DMA is a precise tool for assessing the Tg of lignin and therefore should be considered by rese... Mostrar Tudo |
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Palavras-Chave: |
Análise Mecânica Dinâmica; Análise térmica; Calorimetria Exploratória Diferencial; Temperatura de transição vítrea. |
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Thesagro: |
Lignina. |
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Thesaurus Nal: |
Differential scanning calorimetry; Eucalyptus; Glass transition temperature; Lignin; Thermal analysis. |
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Categoria do assunto: |
K Ciência Florestal e Produtos de Origem Vegetal |
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Marc: |
LEADER 02564naa a2200313 a 4500
001 2177794
005 2025-08-19
008 2025 bl uuuu u00u1 u #d
022 $a1022-9760
024 7 $ahttps://doi.org/10.1007/s10965-025-04485-y$2DOI
100 1 $aLOMONACO, D.
245 $aInnovative application of dynamic mechanical analysis for accurate glass transition determination in technical lignins.$h[electronic resource]
260 $c2025
520 $aSustainable chemistry is driving attention to the use of lignocellulosic materials. Among those, lignin stands out as an alternative for phenolic compounds. Lignin is a powdered amorphous biopolymer, which glass transition temperature (Tg) is commonly assessed by differential scanning calorimetry (DSC). As Tg is related to molecular relaxation of the polymer structure, it varies according to the plant species, isolation method, etc., and many authors report the difficulty in clearly assessing lignin's Tg by DSC. Another technique which is sensitive and precise in determining relaxation processes is Dynamic Mechanical Analysis (DMA) but is usually employed to self-supporting samples. Here, we assessed the Tg of different powdered samples of technical Eucalyptus lignins by DMA and compared it with DSC and chromatographic analysis. The nature of Eucalyptus lignins (MWL, Kraft, Pyrolytic, and Organosolv lignins), heating rate (3, 5, and 10 K min-1), and humidity were evaluated. The results revealed well-defined relaxation processes occurring at temperatures similar to the baseline shift observed in the DSC thermogram, which is typically considered as the Tg. Furthermore, it was found that some factors such as heating rate and humidity did not significantly affect the Tg values obtained by DMA, but it exerts a considerable influence on those obtained by DSC. The main conclusion is that DMA is a precise tool for assessing the Tg of lignin and therefore should be considered by researchers as a new instrument for lignin characterization.
650 $aDifferential scanning calorimetry
650 $aEucalyptus
650 $aGlass transition temperature
650 $aLignin
650 $aThermal analysis
650 $aLignina
653 $aAnálise Mecânica Dinâmica
653 $aAnálise térmica
653 $aCalorimetria Exploratória Diferencial
653 $aTemperatura de transição vítrea
700 1 $aAVELINO, F.
700 1 $aMATOS, M.
700 1 $aLOURENCON, T.
700 1 $aMAGALHAES, W. L. E.
773 $tJournal of Polymer Research$gv. 32, n. 8, 2025.
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Registro original: |
Embrapa Florestas (CNPF) |
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| 1. |  | MCMANUS, C. M.; BRANQUINHO, R. de P.; LOUVANDINI, H.; PAIVA, S. R.; DALLAGO, B. S.; BERTOLI, C. D. Genotype environment interaction in performance Tests in sheep in confinement and at pasture. Ciência Animal Brasileira, v. 13, n. 2, p. 213-220, abr./jun. 2012.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: B - 2 |
| Biblioteca(s): Embrapa Recursos Genéticos e Biotecnologia. |
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| 2. | | CAMPOS, G. S.; BRACCINI NETO, J.; OAIGEN, R. P.; CARDOSO, F. F.; COBUCI, J. A.; KERN, E. L.; CAMPOS, L. T.; BERTOLI, C. D.; McMANUS, C. M. Bioeconomic model and selection indices in Aberdeen Angus cattle. Journal of Animal Breeding and Genetics, Berlin, v. 131, n. 4, p. 305?312, Aug. 2014.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: A - 2 |
| Biblioteca(s): Embrapa Pecuária Sul. |
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| 3. | | CASTANHEIRA, M.; MCMANUS, C. M.; PAULA NETO, J. B. DE; COSTA, M. J. R. P. DA; MENDES, F. D. C.; SERENO, J. R. B.; BÉRTOLI, C. D.; FIORAVANTE, M. C. S. Maternal offspring behaviour in Curraleiro Pé Duro naturalized cattle in Brazil. Revista Brasileira de Zootecnia, v. 42, n. 8, p. 584-591, 2013.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: B - 1 |
| Biblioteca(s): Embrapa Cerrados. |
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| Registros recuperados : 3 | |
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