Surface properties and crystallinity ofPinus taedaandHymenaea stilbocarpatreated at low temperatures in different grain directions

Autor(es)

dos Santos, S. N. C. ^[1] ; de Almeida, T. H. ^[2] ; Sardela, M. R. ^[3] ; Lahr, F. A. R. ^[2] ; Goncalves, D. ^{[1, 4]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Escola Engn Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[3] Univ Illinois, Frederick Seitz Mat Res Labs, 104 S Godwin Ave, Urbana, IL 61801 - USA

^[4] Sardela, M. R., Univ Illinois, Frederick Seitz Mat Res Labs, 104 S Godwin Ave, Urbana, IL 61801 USA.dos Santos, S. N. C., Univ Sao Paulo, Inst Fis Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF THE INDIAN ACADEMY OF WOOD SCIENCE; v. 17, n. 1, p. 46-53, JUN 2020.
• Citações Web of Science: 0

Resumo

Nondestructive methods were employed to characterize longitudinal (L) and transverse (T) sections of Pinus (Pinus taeda) (softwood) and Hymenaea (Hymenaea stilbocarpa) (hardwood) treated at room temperature (25 degrees C) to 100 degrees C, 140 degrees C, and 180 degrees C. Changes in color were verified upon mild heating, regardless of cut direction, with Hymenaea exhibiting the darkest tan. Relatively high values of contact angles were obtained (120 degrees) in water implying that surface wetting decreased even at relatively low temperatures, e.g., 100 degrees C. Differences in heat-treated woods were more noticeable after calculating the surface free energy and its components, with the polar component contributing significantly to the total energy. Crystallinity varied mostly in terms of a meridional pattern in (T) samples. The techniques used in this study seem promising for characterizing anisotropy in woods treated at temperatures lower than 180 degrees C, i.e., before thermal degradation reactions to be likely significant. (AU)

• Processo FAPESP: 14/02766-3 - Sistemas epidérmicos para a análise de biofluídos
• Beneficiário: Debora Goncalves
• Modalidade de apoio: Bolsas no Exterior - Pesquisa
• Processo FAPESP: 13/14262-7 - Filmes nanoestruturados de materiais de interesse biológico
• Beneficiário: Osvaldo Novais de Oliveira Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático