Propriedades de adesivo aplicado em painéis a partir da substituição por lignossulfonato do processo sulfito

Considering the agglomerated panel industries, most of them use synthetic adhesives, especially urea-formaldehyde, and to this end, studies covering the characteristics of alternative materials for the panel industry become important, especially when considering the final cost of the products generated. The present work had as general objective to evaluate the alterations in the chemical structure of the adhesive that could cause possible modifications in its binder properties as a function of the substitution of the adhesive urea-formaldehyde by the lignosulfonate. Therefore, it was determined the basic chemical composition of the lignosulfonate and its chemical bonds by infrared spectroscopy (IR) and the nuclear magnetic resonance (NMR), pure and in composition with different catalysts; the properties of urea-formaldehyde and its modifications such as pH, viscosity, gel time and viscosity. NMR analysis showed the lignosulfonate to the same pattern usually obtained for lignin derivatives in their chemical bonds. The elementary chemical analysis showed high Mg, Ca and Na. The addition of lignosulfonate on urea-formaldehyde caused the adhesive acidification and reduction of viscosity values. The effect on gel time was also affected. However, it was found that the methodology for this type of polymer should be adequate compared to the traditional method, submitting the same to temperatures above 90°C. The results showed that it is possible to use lignosulfonate to replace the urea-formaldehyde adhesive.Considerando a indústria de painéis aglomerados, a maior parte utiliza adesivos sintéticos, especialmente, à base de ureia-formaldeído, e nesse sentido, estudos que englobam as características de materiais alternativas para a indústria de painéis tornam-se importantes, especialmente quando se considera o custo final dos produtos gerados. O presente trabalho teve como objetivo geral avaliar as alterações na estrutura química do adesivo que pudessem provocar possíveis modificações nas suas propriedades ligantes em função da substituição do adesivo ureia-formaldeído pelo lignossulfonato. Para tanto, foi determinada a composição química elementar do lignossulfonato e suas ligações químicas por meio da espectroscopia de infravermelho (IV) e ressonância magnética nuclear (RMN), puro e em composição com diferentes catalisadores; as propriedades da ureia formaldeído e suas modificações como pH, viscosidade, tempo de formação de gel e viscosidade. A análise de RMN mostrou, para o lignossulfonato, o mesmo padrão geralmente obtido para derivados de lignina em suas ligações químicas. A análise química elementar mostrou altos teores de Mg, Ca e Na. A adição de lignossulfonato sobre a ureia-formaldeído causou acidificação no adesivo e redução dos valores de viscosidade. O efeito sobre o tempo de formação de gel também foi afetado, entretanto, verificou-se que a metodologia para esse tipo de polímero, deve ser readequada em relação ao método tradicional, submetendo o mesmo à temperatura superior a 90°C. Os resultados permitiram concluir que é possível a utilização do lignossulfonato em substituição ao adesivo ureia-formaldeído considerando o painel de madeira aglomerada

Produção de painéis de cimento-madeira com adição de diferentes proporções de casca e microssílica.

This work’s objective was to evaluate the effect of three percentages of addition of microsilica (0, 20 and 30%) on the physical and mechanical properties of wood-cement bonded particleboards of Eucalyptus urophylla composed by three wood:bark ratios (100:0, 95:5 and 90:10). Results showed that the most significant effect of the additive on the produced panels was in those containing bark, and that of 20% of additive was more efficient on the physical and mechanical properties.O objetivo deste trabalho foi avaliar o efeito da adição de microssílica em três porcentagens (0, 20 e 30%) sobre as propriedades físicas e mecânicas de painéis cimento-madeira de Eucalyptus urophylla compostos por três relações madeira:casca (100:0, 95:5 e 90:10). Os resultados mostraram que o efeito mais significativo do aditivo sobre os painéis produzidos ocorreu naqueles que continham casca, e que a adição de 20% do aditivo foi mais eficiente sobre as propriedades físicas e mecânicas

PRODUCTION OF WOOD-CEMENT BONDED PARTICLEBOARDS WITH DIFFERENT CONTENTS OF BARK AND MICROSILICA

O objetivo deste trabalho foi avaliar o efeito da adi\ue7\ue3o de micross\uedlica em tr\ueas porcentagens (0, 20 e 30%) sobre as propriedades f\uedsicas e mec\ue2nicas de pain\ue9is cimento-madeira de Eucalyptus urophylla compostos por tr\ueas rela\ue7\uf5es madeira:casca (100:0, 95:5 e 90:10). Os resultados mostraram que o efeito mais significativo do aditivo sobre os pain\ue9is produzidos ocorreu naqueles que continham casca, e que a adi\ue7\ue3o de 20% do aditivo foi mais eficiente sobre as propriedades f\uedsicas e mec\ue2nicas.This work\u2019s objective was to evaluate the effect of three percentages of addition of microsilica (0, 20 and 30%) on the physical and mechanical properties of wood-cement bonded particleboards of Eucalyptus urophylla composed by three wood:bark ratios (100:0, 95:5 and 90:10). Results showed that the most significant effect of the additive on the produced panels was in those containing bark, and that of 20% of additive was more efficient on the physical and mechanical properties

Projeto Radiografia da Amazônia: colorização e estratificação vegetal de imagem SAR

The systematic mapping of the Amazon region have been presented as a great challenge for the Division of Geographical Service (DSG Diretoria de Serviço Geográfico) of the Brazilian Army due to its large territorial extension and the difficulties it presents for the use of conventional techniques. In order to face this challenge and given the importance of the region to Brazil, the DSG is running the project known as "Radiography of the Amazon" (RAM). This project uses imaging technology of Interferometric Synthetic Aperture Radar (InSAR), in the P and X bands, to overcome the problem caused by the presence of permanent clouds in the region. This project has generated a significant amount of images, which allows the description of geographical features of the canopy trees (X band) and at ground level (P band). These images, in the amplitude format, have been used to create grayscale image maps in the 1:50,000 scale. This cartographic material has the disadvantage of absence of color which affect the interpretation and identification of targets. Within this context was developed by DSG, a method of colorization and vegetation stratification, based on techniques of digital image processing to generate color synthetic images by adding the color attribute to the grayscale images generated by the SAR. This paper aims to present this methodology, some results obtained by its use in the RAM project and its potential to highlight information facilitating the interpretation of SAR data.Pages: 2022-202

PRODUCTION OF WOOD-CEMENT BONDED PARTICLEBOARDS WITH DIFFERENT CONTENTS OF BARK AND MICROSILICA

O objetivo deste trabalho foi avaliar o efeito da adição de microssílica em três porcentagens (0, 20 e 30%) sobre as propriedades físicas e mecânicas de painéis cimento-madeira de Eucalyptus urophylla compostos por três relações madeira:casca (100:0, 95:5 e 90:10). Os resultados mostraram que o efeito mais significativo do aditivo sobre os painéis produzidos ocorreu naqueles que continham casca, e que a adição de 20% do aditivo foi mais eficiente sobre as propriedades físicas e mecânicas.This work’s objective was to evaluate the effect of three percentages of addition of microsilica (0, 20 and 30%) on the physical and mechanical properties of wood-cement bonded particleboards of Eucalyptus urophylla composed by three wood:bark ratios (100:0, 95:5 and 90:10). Results showed that the most significant effect of the additive on the produced panels was in those containing bark, and that of 20% of additive was more efficient on the physical and mechanical properties

PRODUCTION OF WOOD-CEMENT BONDED PARTICLEBOARDS WITH DIFFERENT CONTENTS OF BARK AND MICROSILICA

<p>This work’s objective was to evaluate the effect of three percentages of addition of microsilica (0, 20 and 30%) on the physical and mechanical properties of wood-cement bonded particleboards of <em>Eucalyptus urophylla</em> composed by three wood:bark ratios (100:0, 95:5 and 90:10). Results showed that the most significant effect of the additive on the produced panels was in those containing bark, and that of 20% of additive was more efficient on the physical and mechanical properties.</p