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Cláudio Henrique Soares Del Menezzi - One of the best experts on this subject based on the ideXlab platform.
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ACCELERATED LABORATORY TEST OF RUBBERWOOD Oriented STRANDBOARD EXPOSED TO WOOD DECAY FUNGI
Universidade Federal de Santa Maria, 2009Co-Authors: Esmeralda Yoshico Arakaki Okino, Marcus Vinícius Da Silva, Divino Eterno Teixeira, Mário Rabelo De Souza, Marcos Antonio Santana, Cláudio Henrique Soares Del MenezziAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation.
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ENSAIO ACELERADO DE LABORATÓRIO DE CHAPAS OSB DE SERINGUEIRA SUBMETIDAS AO ATAQUE DE FUNGOS APODRECEDORES
Universidade Federal de Santa Maria, 2009Co-Authors: Esmeralda Yoshico Arakaki Okino, Divino Eterno Teixeira, Mário Rabelo De Souza, Marcus Vinícius Da Silva Alves, Marcos Antonio Eduardo Santana, Cláudio Henrique Soares Del MenezziAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation
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Effect of thermal post-treatment on some surface-related properties of Oriented Strandboards
2008Co-Authors: Cláudio Henrique Soares Del Menezzi, Divino Eterno Teixeira, Raquel Ribeiro, Gerson Henrique Sternadt, Esmeralda Yoshico Arakaki OkinoAbstract:A very promising method for improving the dimensional stability of Oriented strandboard (OSB) has been studied in Brazil since 2001. According to this method, the OSB is thermally treated under mild conditions using a hot-press, where it is reheated without high level of compression stress. The properties of the treated OSB panels are different from and enhanced compared to those untreated ones. It means that the treated OSB can be used in more severe uses, like concrete formwork. This paper aims to evaluate the effect of the proposed thermal treatment on nail-holding capability and on surface hardness of OSB. Samples from 42 commercials OSB were thermally treated according to two levels of temperature (190°C and 220°C) and three heating times (12, 16 and 20 min) using a single opening hot-press. For comparison, control panels were kept untreated. The following surface-related properties were evaluated: Janka hardness, nail-holding capability in a plane normal to the surface, in the edge of the panel, water absorption and thickness swelling (TS) of edge sealed samples, and four surface roughness parameters. According to the Dunnett test, there were significant differences between treated and untreated panels for nail-holding, dimensional stability and surface roughness. The factorial ANOVA identified that the temperature was the main factor governing these properties while the duration of the treatment had lesser effect. It was concluded that the proposed thermal treatment improved significantly dimensional stability and did not affect adversely the nail-holding capability and surface roughness of the treated OSB.
Esmeralda Yoshico Arakaki Okino - One of the best experts on this subject based on the ideXlab platform.
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ACCELERATED LABORATORY TEST OF RUBBERWOOD Oriented STRANDBOARD EXPOSED TO WOOD DECAY FUNGI
Universidade Federal de Santa Maria, 2009Co-Authors: Esmeralda Yoshico Arakaki Okino, Marcus Vinícius Da Silva, Divino Eterno Teixeira, Mário Rabelo De Souza, Marcos Antonio Santana, Cláudio Henrique Soares Del MenezziAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation.
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ENSAIO ACELERADO DE LABORATÓRIO DE CHAPAS OSB DE SERINGUEIRA SUBMETIDAS AO ATAQUE DE FUNGOS APODRECEDORES
Universidade Federal de Santa Maria, 2009Co-Authors: Esmeralda Yoshico Arakaki Okino, Divino Eterno Teixeira, Mário Rabelo De Souza, Marcus Vinícius Da Silva Alves, Marcos Antonio Eduardo Santana, Cláudio Henrique Soares Del MenezziAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation
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Effect of thermal post-treatment on some surface-related properties of Oriented Strandboards
2008Co-Authors: Cláudio Henrique Soares Del Menezzi, Divino Eterno Teixeira, Raquel Ribeiro, Gerson Henrique Sternadt, Esmeralda Yoshico Arakaki OkinoAbstract:A very promising method for improving the dimensional stability of Oriented strandboard (OSB) has been studied in Brazil since 2001. According to this method, the OSB is thermally treated under mild conditions using a hot-press, where it is reheated without high level of compression stress. The properties of the treated OSB panels are different from and enhanced compared to those untreated ones. It means that the treated OSB can be used in more severe uses, like concrete formwork. This paper aims to evaluate the effect of the proposed thermal treatment on nail-holding capability and on surface hardness of OSB. Samples from 42 commercials OSB were thermally treated according to two levels of temperature (190°C and 220°C) and three heating times (12, 16 and 20 min) using a single opening hot-press. For comparison, control panels were kept untreated. The following surface-related properties were evaluated: Janka hardness, nail-holding capability in a plane normal to the surface, in the edge of the panel, water absorption and thickness swelling (TS) of edge sealed samples, and four surface roughness parameters. According to the Dunnett test, there were significant differences between treated and untreated panels for nail-holding, dimensional stability and surface roughness. The factorial ANOVA identified that the temperature was the main factor governing these properties while the duration of the treatment had lesser effect. It was concluded that the proposed thermal treatment improved significantly dimensional stability and did not affect adversely the nail-holding capability and surface roughness of the treated OSB.
Okino, esmeralda Yoshico Arakaki - One of the best experts on this subject based on the ideXlab platform.
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Accelerated laboratory test of rubberwood Oriented strandboard exposed to wood decay fungi
Centro de Pesquisas Florestais - CEPEF Departamento de Ciências Florestais - DCFL Programa de Pós Graduação em Engenharia Florestal - PPGEF, 2010Co-Authors: Okino, esmeralda Yoshico Arakaki, Teixeira, divino Eterno, Menezzi, Cláudio Henrique Soares Del, Alves, Marcus Vinícius Da Silva, De Souza, Mário Rabelo, Santana, Marcos Antonio EduardoAbstract:O objetivo do trabalho foi avaliar a resistência natural de chapas de partículas orientadas (OSB) confeccionadas com partículas de Hevea brasiliensis Müll.Arg. aderidas com as resinas sintéticas uréiaformaldeído (UF) e fenol-formaldeído (FF), a 5% e 8%, expostas a fungos xilófagos em condições de laboratório. No ensaio acelerado de laboratório as amostras foram submetidas ao ataque dos fungos de podridão-parda Gloeophyllum trabeum (Pers. : Fr.) Murril, Coniophora puteana (Schumach. : Fr.) P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill e também aos fungos de podridão-branca, Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. e Phanerochaete chrysosporium Burds. Dentre os fungos de podridão-parda, o Gloeophyllum trabeum causou a maior perda de massa nos corpos-de-prova testados. Dentre os fungos de podridão-branca, Trametes versicolor, Phanerochaete chrysosporium e Ganoderma applanatum causaram as maiores perdas de massa, sem diferença significativa para o Gloeophyllum trabeum. A resina FF proporcionou maior resistência à ação dos fungos nas chapas OSB, o mesmo fato ocorrendo com o maior teor de resina. O fungo Coniophora puteana foi altamente sensível ao tipo de resina aplicado, enquanto o Bjerkandera fumosa demonstrou reduzida ação nas concentrações mais altas de ambas as resinas. O fungo Fomes annosus apresentou degradação insignificante para todos os tratamentos de chapas OSB.This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation
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Ensaio acelerado de laboratório de chapas OSB de seringueira submetidas ao ataque de fungos apodrecedores
'Universidad Federal de Santa Maria', 2009Co-Authors: Okino, esmeralda Yoshico Arakaki, Marcus Vinícius Da Silva, Mário Rabelo De Souza, Teixeira, divino Eterno, Santana, Marcos Antonio, Menezzi, Cláudio Henrique Soares DelAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation.O objetivo do trabalho foi avaliar a resistência natural de chapas de partículas orientadas (OSB) confeccionadas com partículas de Hevea brasiliensis Müll.Arg. aderidas com as resinas sintéticas uréia-formaldeído (UF) e fenol-formaldeído (FF), a 5% e 8%, expostas a fungos xilófagos em condições de laboratório. No ensaio acelerado de laboratório as amostras foram submetidas ao ataque dos fungos de podridão-parda Gloeophyllum trabeum (Pers. : Fr.) Murril, Coniophora puteana (Schumach. : Fr.) P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill e também aos fungos de podridão-branca, Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. e Phanerochaete chrysosporium Burds. Dentre os fungos de podridão-parda, o Gloeophyllum trabeum causou a maior perda de massa nos corpos-de-prova testados. Dentre os fungos de podridão-branca, Trametes versicolor, Phanerochaete chrysosporium e Ganoderma applanatum causaram as maiores perdas de massa, sem diferença significativa para o Gloeophyllum trabeum. A resina FF proporcionou maior resistência à ação dos fungos nas chapas OSB, o mesmo fato ocorrendo com o maior teor de resina. O fungo Coniophora puteana foi altamente sensível ao tipo de resina aplicado, enquanto o Bjerkandera fumosa demonstrou reduzida ação nas concentrações mais altas de ambas as resinas. O fungo Fomes annosus apresentou degradação insignificante para todos os tratamentos de chapas OSB
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ACCELERATED LABORATORY TEST OF RUBBERWOOD Oriented STRANDBOARD EXPOSED TO WOOD DECAY FUNG
'Universidad Federal de Santa Maria', 2009Co-Authors: Okino, esmeralda Yoshico Arakaki, Alves, marcus Vinícius Da Silva, Teixeira, divino Eterno, mário Rabelo De ,souza, Santana, marcos Antonio Eduardo, Menezzi, cláudio Henrique Soares DelAbstract:RESUMO O objetivo do trabalho foi avaliar a resistência natural de chapas de partículas orientadas (OSB) confeccionadas com partículas de Hevea brasiliensis Müll.Arg. aderidas com as resinas sintéticas uréia- formaldeído (UF) e fenol-formaldeído (FF), a 5% e 8%, expostas a fungos xilófagos em condições de laboratório. No ensaio acelerado de laboratório as amostras foram submetidas ao ataque dos fungos de podridão-parda Gloeophyllum trabeum (Pers. : Fr.) Murril, Coniophora puteana (Schumach. : Fr.) P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill e também aos fungos de podridão-branca, Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. e Phanerochaete chrysosporium Burds. Dentre os fungos de podridão-parda, o Gloeophyllum trabeum causou a maior perda de massa nos corpos-de-prova testados. Dentre os fungos de podridão-branca, Trametes versicolor, Phanerochaete chrysosporium e Ganoderma applanatum causaram as maiores perdas de massa, sem diferença significativa para o Gloeophyllum trabeum. A resina FF proporcionou maior resistência à ação dos fungos nas chapas OSB, o mesmo fato ocorrendo com o maior teor de resina. O fungo Coniophora puteana foi altamente sensível ao tipo de resina aplicado, enquanto o Bjerkandera fumosa demonstrou reduzida ação nas concentrações mais altas de ambas as resinas. O fungo Fomes annosus apresentou degradação insignificante para todos os tratamentos de chapas OSB.ABSTRACT This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation
M.a.e. Santana - One of the best experts on this subject based on the ideXlab platform.
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Thermal modification of consolidated Oriented Strandboards: effects on dimensional stability, mechanical properties, chemical composition and surface color
European Journal of Wood and Wood Products, 2009Co-Authors: C.h.s. Del Menezzi, I. Tomaselli, E.y.a. Okino, D.e. Teixeira, M.a.e. SantanaAbstract:The objective of this paper was to propose a thermal post-treatment to improve the dimensional stability of Oriented strandboard (OSB). Commercial OSB panels were obtained from an industrial batch and thermally treated in a single opening hot-press at two temperature levels (190 and 220 °C) and three duration times (12, 16 and 20 min). Dimensional stability, mechanical properties, chemical composition and surface color were studied. The results pointed-out that the proposed treatment can be applied to significantly improve the OSB dimensional stability by reducing thickness swelling, water absorption, and equilibrium moisture content in comparison to the untreated board. The mechanical properties were partially affected with reduction in modulus of rupture and without any adverse effect on the other properties. Chemical degradation occurred, mainly in relation to hemicelluloses contents, reducing equilibrium moisture content. The board surface became darker and this characteristic was correlated with the observed properties improvement. Dimensional stability properties were affected by both temperature and duration of the treatment, while the others mainly by temperature. The proposed thermal treatment can be recommended as a post-treatment to improve the OSB performance. Ziel dieser Studie war es, OSB-Platten einer nachträglichen Wärmebehandlung zu unterziehen, um deren Dimensionsstabilität zu verbessern. Handelsübliche OSB-Platten aus industrieller Fertigung wurden in einer Einetagen-Heißpresse bei zwei unterschiedlichen Temperaturen (190 und 220 °C) unterschiedlich lang (12, 16 und 20 Min) wärmebehandelt. Untersucht wurden die Dimensionsstabilität, die mechanischen Eigenschaften, die chemische Zusammensetzung und die Oberflächenfarbe. Die Ergebnisse zeigten, dass das vorgeschlagene Verfahren geeignet ist, durch Reduzierung der Dickenquellung, der Wasseraufnahme und der Gleichgewichtsfeuchte die Dimensionsstabilität von OSB-Platten signifikant zu verbessern. Die mechanischen Eigenschaften waren davon teilweise betroffen. Die Biegefestigkeit nahm ab, die anderen Eigenschaften wurden nicht beeinträchtigt. Ein chemischer Abbau wurde festgestellt: im Wesentlichen bezüglich des Hemicellulosegehalts, wodurch die Gleichgewichtsfeuchte reduziert wurde. Die Holzoberfläche wurde dunkler, und war mit den verbesserten Eigenschaften der OSB-Platten korreliert. Die Dimensionsstabilität wurde sowohl von der Temperatur als auch von der Behandlungsdauer beeinflusst, während die anderen Eigenschaften nur von der Temperatur beeinflusst wurden. Die vorgeschlagene Wärmebehandlung kann als ein nachträgliches Behandlungsverfahren zur Verbesserung der OSB-Eigenschaften empfohlen werden.
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Thermal modification of consolidated Oriented Strandboards: effects on dimensional stability, mechanical properties, chemical composition and surface color
European Journal of Wood and Wood Products, 2009Co-Authors: C. H. S. Del Menezzi, I. Tomaselli, E.y.a. Okino, D.e. Teixeira, M.a.e. SantanaAbstract:The objective of this paper was to propose a thermal post-treatment to improve the dimensional stability of Oriented strandboard (OSB). Commercial OSB panels were obtained from an industrial batch and thermally treated in a single opening hot-press at two temperature levels (190 and 220 °C) and three duration times (12, 16 and 20 min). Dimensional stability, mechanical properties, chemical composition and surface color were studied. The results pointed-out that the proposed treatment can be applied to significantly improve the OSB dimensional stability by reducing thickness swelling, water absorption, and equilibrium moisture content in comparison to the untreated board. The mechanical properties were partially affected with reduction in modulus of rupture and without any adverse effect on the other properties. Chemical degradation occurred, mainly in relation to hemicelluloses contents, reducing equilibrium moisture content. The board surface became darker and this characteristic was correlated with the observed properties improvement. Dimensional stability properties were affected by both temperature and duration of the treatment, while the others mainly by temperature. The proposed thermal treatment can be recommended as a post-treatment to improve the OSB performance.
Divino Eterno Teixeira - One of the best experts on this subject based on the ideXlab platform.
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ACCELERATED LABORATORY TEST OF RUBBERWOOD Oriented STRANDBOARD EXPOSED TO WOOD DECAY FUNGI
Universidade Federal de Santa Maria, 2009Co-Authors: Esmeralda Yoshico Arakaki Okino, Marcus Vinícius Da Silva, Divino Eterno Teixeira, Mário Rabelo De Souza, Marcos Antonio Santana, Cláudio Henrique Soares Del MenezziAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation.
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ENSAIO ACELERADO DE LABORATÓRIO DE CHAPAS OSB DE SERINGUEIRA SUBMETIDAS AO ATAQUE DE FUNGOS APODRECEDORES
Universidade Federal de Santa Maria, 2009Co-Authors: Esmeralda Yoshico Arakaki Okino, Divino Eterno Teixeira, Mário Rabelo De Souza, Marcus Vinícius Da Silva Alves, Marcos Antonio Eduardo Santana, Cláudio Henrique Soares Del MenezziAbstract:This work aimed to evaluate the natural durability of Oriented Strandboards (OSB) manufactured with strands of Hevea brasiliensis Müll.Arg. bonded with 5% and 8% of urea-formaldehyde (UF) and phenol-formadehyde (FF) resins, exposed to xilophagous fungi under laboratory conditions. In accelerated laboratory test decay, samples of OSB were exposed to the following fungi: the brown-rot fungi Gloeophyllum trabeum (Pers. ex Fries) Murr., Coniophora puteana (Schumach. : Fr.)P. Karst., Meruliporia incrassata (Berk. & M.A. Curtis) Murrill as well as the white-rot fungi Fomes annosus (Fr. : Fr.) Cooke, Trametes versicolor (L. : Fr.) Pilát, Ganoderma applanatum (Pers.) Pat., Bjerkandera fumosa (Pers. : Fr.) P. Karst. and Phanerochaete chrysosporium Burds. Among the brown-rot fungi, the Gloeophyllum trabeum was the most aggressive, showing the highest loss of mass. Trametes versicolor and Ganoderma applanatum confirmed the preference for broadleave species. All Oriented Strandboards at lower UF resin contents were more degraded by Phanerochaete chrysosporium, Trametes versicolor, Ganoderma applanatum, Merulia incrassata, Coniophora puteana and Gloeophyllum trabeum, with high rate of loss of mass. Coniophora puteana showed small loss of mass when FF resin was applied. Bjerkandera fumosa showed low loss of mass only at higher resin content. Oriented Strandboards exposed to Coniophora puteana showed insignificant OSB degradation
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Effect of thermal post-treatment on some surface-related properties of Oriented Strandboards
2008Co-Authors: Cláudio Henrique Soares Del Menezzi, Divino Eterno Teixeira, Raquel Ribeiro, Gerson Henrique Sternadt, Esmeralda Yoshico Arakaki OkinoAbstract:A very promising method for improving the dimensional stability of Oriented strandboard (OSB) has been studied in Brazil since 2001. According to this method, the OSB is thermally treated under mild conditions using a hot-press, where it is reheated without high level of compression stress. The properties of the treated OSB panels are different from and enhanced compared to those untreated ones. It means that the treated OSB can be used in more severe uses, like concrete formwork. This paper aims to evaluate the effect of the proposed thermal treatment on nail-holding capability and on surface hardness of OSB. Samples from 42 commercials OSB were thermally treated according to two levels of temperature (190°C and 220°C) and three heating times (12, 16 and 20 min) using a single opening hot-press. For comparison, control panels were kept untreated. The following surface-related properties were evaluated: Janka hardness, nail-holding capability in a plane normal to the surface, in the edge of the panel, water absorption and thickness swelling (TS) of edge sealed samples, and four surface roughness parameters. According to the Dunnett test, there were significant differences between treated and untreated panels for nail-holding, dimensional stability and surface roughness. The factorial ANOVA identified that the temperature was the main factor governing these properties while the duration of the treatment had lesser effect. It was concluded that the proposed thermal treatment improved significantly dimensional stability and did not affect adversely the nail-holding capability and surface roughness of the treated OSB.
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effect of thermal post treatment on some surface related properties of Oriented Strandboards utjecaj toplinske obrade na neka svojstva povrsine iverice s orijentiranim iverjem
2008Co-Authors: Henrique Soares, Divino Eterno Teixeira, Raquel Ribeiro, Gerson Henrique Sternadt, Del Menezzi, Esmeralda Yoshico, Arakaki OkinoAbstract:SA@ETAKVrlo obe}avaju}a metoda za pobolj{anje dimenzijske stabilnosti plo~a iverica s orijentiranim iver- jem (OSB plo~a) prou~ava se u Brazilu od 2001. godine. Prema toj metodi, OSB plo~a se obra|uje toplinom u umje- renim uvjetima, uporabom vru}e pre{e, pri ~emu se ponovo zagrijava bez velikog pritiska. Svojstva toplinski obra|enih OSB plo~a pobolj{ana su u odnosu prema neobra|enim plo~ama. To zna~i da se termi~ki obra|ene OSB plo~e mogu rabiti i u zahtjevnijim uvjetima, npr. kao betonske oplate. Cilj ovog rada bio je procijeniti utjecaj meto- de toplinske obrade OSB plo~a na ~vrsto}u dranja ~avala te povr{insku tvrdo}u tretiranih plo~a. Uzorci izra|eni od komercijalne OSB plo~e toplinski su obra|eni u vru}oj pre{i na dvije razine temperature (190 °C i 220 °C) i tri vremena zagrijavanja (12, 16 i 20 min). Za usporedbu su uzeti kontrolni uzorci koji nisu obra|ivani. Istraivana su