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Registro Completo |
Biblioteca(s): |
Embrapa Florestas. |
Data corrente: |
18/10/2019 |
Data da última atualização: |
17/11/2020 |
Tipo da produção científica: |
Artigo em Periódico Indexado |
Autoria: |
LOURENÇON, T. V.; ALAKURTII, S.; VIRTANEN, T.; JÄÄSKELÄINEN, A.-S.; LIITIÄ, T.; HUGHES, M.; MAGALHAES, W. L. E.; BOLZON DE MUNIZ, G. I.; TAMMINEN, T. |
Afiliação: |
Tainise V. Lourençon, Aalto UniversitY; Sami Alakurtti, VTT Technical Research Centre of Finland; Tommi Virtanen, VTT Technical Research Centre of Finland; Anna-Stiina Jääskeläinen, VTT Technical Research Centre of Finland; Tiina Liitiä, VTT Technical Research Centre of Finland; Mark Hughes, Aalto University; WASHINGTON LUIZ ESTEVES MAGALHAES, CNPF; Graciela I. Bolzon de Muniz, UFPR; Tarja Tamminen, VTT Technical Research Centre of Finland. |
Título: |
Phenol-formaldehyde resins with suitable bonding strength synthesized from "less-reactive" hardwood lignin fractions. |
Ano de publicação: |
2020 |
Fonte/Imprenta: |
Holzforschung, v. 74, n. 2, p. 175-183, Feb. 2020. |
DOI: |
10.1515/hf-2018-0203 |
Idioma: |
Inglês |
Conteúdo: |
The substitution of phenol by lignin in phenol-formaldehyde (PF) resins is one of the most promising end uses of lignin valorization. Lignin from grasses and softwood has been the focus of the studies in this field as they present a higher number of theoretical reactive sites for resin synthesis. Herein we examined the composition and chemical reactivity of ?less-reactive? hardwood lignin fractions and their performance in PF resins, synthesized by substituting 50 wt% of the phenol with lignin. Before resin synthesis, the samples were hydroxymethylated and the maximum formaldehyde consumption was recorded. By doing so, we observed that hardwood fractions consumed formaldehyde close to the theoretical calculation, whereas the reference softwood lignin consumed only about ¼ of the theoretical value. In the resin synthesis, we added formaldehyde to the formulation according to the measured maximum formaldehyde consumption. Thus, low values of free formaldehyde in lignin-PF (LPF) resins were achieved (<0.23%). Moreover, the resin bonding strength displayed similar performance irrespective of whether the LPF resins were made with softwood or hardwood lignin (range of 3.4?4.8 N mm?2 at 150°C and 45?480 s of press time). Furthermore, we concluded that hardwood kraft lignins present no disadvantage compared to softwood lignins in PF resin applications, which have significant practical implications. |
Palavras-Chave: |
Formaldehyde consumption; Formaldeído; Kraft; Phenolic resins; Reactive sites; Resina fenólica; Technical lignin. |
Categoria do assunto: |
X Pesquisa, Tecnologia e Engenharia |
Marc: |
LEADER 02355naa a2200313 a 4500 001 2113225 005 2020-11-17 008 2020 bl uuuu u00u1 u #d 024 7 $a10.1515/hf-2018-0203$2DOI 100 1 $aLOURENÇON, T. V. 245 $aPhenol-formaldehyde resins with suitable bonding strength synthesized from "less-reactive" hardwood lignin fractions.$h[electronic resource] 260 $c2020 520 $aThe substitution of phenol by lignin in phenol-formaldehyde (PF) resins is one of the most promising end uses of lignin valorization. Lignin from grasses and softwood has been the focus of the studies in this field as they present a higher number of theoretical reactive sites for resin synthesis. Herein we examined the composition and chemical reactivity of ?less-reactive? hardwood lignin fractions and their performance in PF resins, synthesized by substituting 50 wt% of the phenol with lignin. Before resin synthesis, the samples were hydroxymethylated and the maximum formaldehyde consumption was recorded. By doing so, we observed that hardwood fractions consumed formaldehyde close to the theoretical calculation, whereas the reference softwood lignin consumed only about ¼ of the theoretical value. In the resin synthesis, we added formaldehyde to the formulation according to the measured maximum formaldehyde consumption. Thus, low values of free formaldehyde in lignin-PF (LPF) resins were achieved (<0.23%). Moreover, the resin bonding strength displayed similar performance irrespective of whether the LPF resins were made with softwood or hardwood lignin (range of 3.4?4.8 N mm?2 at 150°C and 45?480 s of press time). Furthermore, we concluded that hardwood kraft lignins present no disadvantage compared to softwood lignins in PF resin applications, which have significant practical implications. 653 $aFormaldehyde consumption 653 $aFormaldeído 653 $aKraft 653 $aPhenolic resins 653 $aReactive sites 653 $aResina fenólica 653 $aTechnical lignin 700 1 $aALAKURTII, S. 700 1 $aVIRTANEN, T. 700 1 $aJÄÄSKELÄINEN, A.-S. 700 1 $aLIITIÄ, T. 700 1 $aHUGHES, M. 700 1 $aMAGALHAES, W. L. E. 700 1 $aBOLZON DE MUNIZ, G. I. 700 1 $aTAMMINEN, T. 773 $tHolzforschung$gv. 74, n. 2, p. 175-183, Feb. 2020.
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1. |  | ABUD, Lucas Jacomini; JULIANO, R. S.; COSTA, Gustavo Lage; MAGGIOLI, M.; SANTIN, A. P. I; FIORAVANTI, Maria Clorinda Soares. Eletroforese das proteínas séricas de animais da raça Curraleiro: comparação com outras raças bovinas. (Serum protein electrophoresis of Curraleiro bovine: comparison with other bovine breeds.) In: CONGRESSO BRASILEIRO DE BUIATRIA, 7., 2007, Curitiba, [Resumo expandido] Curitiba, PR, 2007. 1 p.Tipo: Artigo em Anais de Congresso / Nota Técnica |
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2. |  | SANTIN, A. P. I.; JULIANO, R. S.; SILVA, A. C.; OLIVEIRA, V. S. F. de; KIPNIS, ANA PAULA JUNQUEIRA; BRITO, W. M. E. D. de; FIORAVANTI, M. C. S. Soroepidemiologia de Neospora Caninum e Toxoplasma Gondii em bovinos da raça curraleiro curraleiro cattle breed health status for neosporosis and toxoplasmosis. Ciência animal brasileira, Goiânia, v.18, p. 1-8, 2017.Tipo: Artigo em Periódico Indexado | Circulação/Nível: B - 2 |
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