Setsuo Iwakiri

Pinus spp. na produção de painéis de partículas orientadas (OSB)

This work had the objective to study the species effects, and the wax addition in the OSB panels properties. The final conclusion was that the studied species are homogeneous among themselves and they produce similar quality panels. The produced panels attended to the minimum specifications of the CSA 0437.0 Canadian standard.

Utilização de madeiras de Eucalyptus grandis e Eucalyptus dunnii para produção de painéis de partículas orientadas – OSB.

This study was developed to evaluate the feasibility of OSB manufacturing using woods of Eucalyptus grandis and Eucalyptus dunnii. Boards with nominal density of 0,70 g/cm³ and 1,0 g/cm³ were manufactured in laboratory, using 100% of wood particles from Pinus taeda, Eucalyptus grandis and Eucalyptus dunnii, and mixtures of 50% of Pinus taeda in the internal layer of the board, with 50% of Eucalyptus grandis and 50% of Eucalyptus dunnii . The boards of Eucalyptus grandis with density of 0,70 g/cm³, as standard board density, showed the values of properties compatible with the requirements of the Canadian and European Standards and also in relation of boards manufactured from Pinus taeda. The results of the mechanical properties showed an increase in the MOE and MOR in static bending with the increase in the board density, opening the possibility to use the high density OSB for applications requiring higher strength. The results of this research indicate that wood of Eucalyptus grandis can be used as alternative specie to OSB manufacturing in the Brazil.

Avaliação da qualidade do compensado fenólico de Eucalyptus grandis .

This research’s main objective is to evaluate the quality of Eucalyptus grandis’ manufactured plywood for external use. In order to make comparisons, plywood of Pinus taeda and Araucaria angustifolia were also manufactured, using phenol-formaldehyde resin with two formulations. The plywoods of Eucalyptus grandis showed higher specific gravity and lesser thickness reduction in comparison with the other two species. The results of shear bonding tests were statistically the same between all species. The values of MOR and MOE of Eucalyptus grandis were statistically the same in comparison with Araucaria angustifolia and higher than Pinus taeda. In relation to effects of different formulations of adhesive, no differences for all evaluated properties were verified excluding water soaking shear bonding test.

Produção de painéis aglomerados homogêneos e multicamadas de Melia azedarach (Cinamomo) e Pinus taeda com diferentes teores de resina

This research was developed to evaluate the quality of homogeneous and multilayer particleboards manufactured from Melia azedarach wood and Pinus taeda with different resin contents. The experimental boards were manufactured with the nominal density of 0,75 g/cm³, using the urea-formaldehyde resin in the proportion of 6% and 8% (solid content based on oven dried wood particles) in the internal layer and 8% and 10% in the external layers. The boards were pressed at the specific pressure of 40 kgf/cm², temperature of 160oC and press time of 8 minutes. The evaluations of the physical and mechanical properties of the boards showed the high potentiality of Melia azedarach for particleboard manufacture. The increase of resin content in the internal and external layers improved the properties of water absorption and thickness swelling. However, the mechanical properties were not affected.

Caracterização de compósitos produzidos com polietileno de alta densidade (HDPE) e serragem da indústria moveleira – parte II – extrusão em dupla-rosca

In this work, wood plastic composites made of HDPE and different types of wood sawdust generate at furniture industries are characterised. The equipment used was a 19 mm co-rotating twin-screw extruder, complementing previous studies where the composites were mixed using a single-screw extruder. Temperatures of 180oC were applied at the five heating zones, rotating at 150 rpm with a flux of 1 kg.h -1 . Residues of MDF, of loblolly pine and of eucalypt wood were used, and were mixed into the HDPE with a coupling agent (anhydride maleic). Physical characterization of the composites was performed by differential scanning calorimetry (DSC) and by scanning electronic microscopy. In addition, the mechanical properties of tension, static bending and impact were analysed, according to ASTM D638, D790 and D256. All types of sawdust acted as a nucleate agent, since the composites showed a crystallinity index higher than pure HDPE. Also, it was observed that the type of sawdust influenced fibre’s dispersion in the polymeric matrix. The mechanical tests showed differences in the properties of the composites made of different types of sawdust. In general, inclusion of MDF sawdust resulted in composites with higher bending strength and impact work than those containing eucalypt and pine. Comparing results obtained using a single-screw extruder and values obtained in this study, it can be concluded that the properties of the wood are more effectively transferred to the composite using a double-screw extruder.

Potencial de uso de espécies de pinus tropicais para produção de painéis cimento-madeira

This study aimed to evaluate the potential use of wood of four tropical pine species for the production of wood-cement panels. The species were Pinus caribaea, Pinus maximinioi, Pinus oocarpa and Pinus tecunumanii. Pinus taeda was used as control. Experimental panels were produced with a density of 1.20 g / cm3 and wood: cement ratio of 1:2.5 and 1:3.0. The panels were pressed with a specific pressure of 4 MPa at room temperature, pressing time / Clipping of 24 hours and maturing time of 28 days. The quality of the panels was evaluated by testing the physical and mechanical properties according to the European standard CEN. The wood: cement ratio did not affect significantly the properties of the panels. Based on comparative evaluations with the values obtained for the control species and data presented in the literature, it can be said that the four tropical pine species are potentially usable for the production of cement-wood panels.

Feasibility of Cordia trichotoma (Vell.) wood and its by-products for particleboard manufacturing

ABSTRACT The wood panel industry uses a large volume of wood and it is essential to research the use of new tree species for these types of products. As such, the aim of this study was to evaluate the feasibility of Cordia trichotoma (Vell.) wood, both on its own and as a mixture with Pinus spp., as well as to understand the effect on particleboard quality when adding the species’ bark and shavings. The experimental design included nine treatments that assessed various mixture proportations of C. trichotoma and Pinus; for example, 10% bark, and 10% shavings of C. trichotoma with Pinus spp. and C. trichotoma particles, as well as mixtures of these two species in proportions of 25/75%, 50%/50%, and 75/25%. The results indicate that the Cordia trichotoma specie is technically feasible when manufacturing particleboards in pure form. The incorporation of bark (at 10% of the mixture) is also technically feasible. It is also feasible to use the shavings of C. trichotoma. In general, all treatments produced outputs that showed dimensional stability and mechanical strength statistically equal or higher than control treatments (Pinus spp.); thus, these products may be used for non-structural applications in dry and/or moist conditions.

Influência de diferentes níveis de acetilação nas propriedades físico-mecânicas de aglomerados e painéis madeira-cimento

O uso de particulas de madeira, quimicamente modificadas na producao de paineis de madeira reconstituida, pode, ao mesmo tempo, afetar positivamente a estabilidade dimensional dos paineis, como afetar negativamente a ligacao interna. Objetivou-se, neste trabalho, encontrar o ponto otimo de acetilacao para paineis aglomerados e madeira-cimento. Foram utilizadas particulas industriais de Pinus taeda acetiladas a 8, 15 e 20% na producao de aglomerados com resina ureia-formaldeido e corpos de prova de madeira-cimento pelo processo de vibrocompactacao. Foram avaliadas as propriedades de absorcao de agua, inchamento de espessura e ligacao interna dos paineis aglomerados de acordo com as normas europeias EN 317 e EN 319. Paineis aglomerados produzidos com particulas acetiladas acima de 15% apresentaram menores valores de absorcao de agua e inchamento de espessura. Contudo, o uso da madeira quimicamente modificada afetou negativamente a ligacao interna dos paineis. Esse fenomeno pode ser explicado pelo comportamento semelhante da resina com a agua, assim, a acetilacao em niveis altos inviabiliza a ligacao entre adesivo e aderente. Para os corpos de prova de madeira-cimento, a ligacao interna melhorou com o aumento dos niveis de acetilacao. Porem a inibicao a cura do cimento aumentou em particulas com graus de acetilacao superior a 8%.

Avaliação Colorimétrica de Aglomerados Produzidos com Partículas de Madeira de Sequoia sempervirens e Pinus taeda Submetidos ao Intemperismo Natural / Outdoor Weathering Evaluation of Particleboards Manufactured from Sequoia sempervirens and Pinus taeda Wood

The aim of this work was to establish the effect of using different amounts of Sequoia sempervirens and Pinus taeda wood particles on the colorimetric properties of particleboard and to evaluate the color change after outdoor weathering for six months. The colorimetric properties were measure according to the CIE-L*a*b* 1976 system. The results indicated a direct relation between the proportion of Sequoia sempervirens wood particles used in the blend and the red pigment values (a*) and an indirect relation with the yellow pigment (b*). Thus the final color of a particleboard can be predicted by controlling the amount of particles from the different species used in particleboard production. However, natural weathering for 4 months is sufficient to decrease a* and b* values and eliminate the color difference between the particleboards.

Avaliação da qualidade de painéis compensados de Pinus maximinoi , Pinus oocarpa e Pinus tecunumannii com diferentes composições estruturais

This study was developed to evaluate the effects of different compositions of plywood of Pinus maximinoi, Pinus oocarpa e Pinus tecunumannii. Were manufactured in laboratory plywood composed by seven veneer with 3,0 mm thickness, with standard composition, longitudinal reinforced composition and transversal reinforced composition. Were used for veneer gluing the phenol- formaldehyde resin with the following formulation in parts of weight: resin = 100, extender = 10 and water = 10. The amount of glue spread was 160 g/m² (one side layer). The boards were pressed at temperature of 150oC, specific pressure of 15 kgf/ cm² and press time of 15 minutes. Were realized static bending tests in the parallel and cross direction. The boards of Pinus maximinoi showed better results in MOE and MOR, parallel and cross direction in comparison to boards of Pinus oocarpa and Pinus tecunumannii. The boards made from three species showed satisfactory results of MOE and MOR, parallel and cross direction, in comparison to commercial plywood of Pinus taeda. The veneer reinforced in to parallel and cross direction not influenced significantly in the results of MOE and MOR parallel direction. The longitudinal veneer reinforced plywood affects poorly the results of MOE and MOR in the cross direction.