Painéis MDP produzidos com resíduos de extração de celulose

Abstract

RESUMO: Muitas alternativas vêm sendo estudadas sobre o emprego de resíduos agrícolas, agroindustriais e florestais na produção de painéis aglomerados na tentativa de aproveitar os resíduos oriundos desses ramos, que por muitas vezes geram problemas ambientais devido à sua destinação incorreta. Dessa forma, este trabalho teve por objetivo avaliar o potencial de utilização do resíduo gerado durante o processo de produção da celulose (UKP), na fabricação de painéis MDP (Medium Density Particleboard). As proporções utilizadas para a substituição da madeira de Pinus oocarpa pelo resíduo foram de 15, 30, 45 e 60% (em massa), utilizando o adesivo ureia-formaldeído. Foram realizados os ensaios de densidade aparente (DA), absorção de água após duas e vinte e quatro horas de imersão (AA2h e AA24h), inchamento em espessura após duas e vinte e quatro horas de imersão (IE2h e IE24h), ligação interna (LI), e módulo de elasticidade (MOE) e módulo de ruptura (MOR) à flexão estática. A utilização de partículas de resíduo UKP para a produção de painéis MDP se mostrou prejudicial, uma vez que acarretou na diminuição das propriedades mecânicas e no aumento dos valores de absorção de água e inchamento em espessura.Palavras-chave: material lignocelulósico; propriedades físico-mecânicas; ureia-formaldeído MDP panels produced with pulp extraction residues ABSTRACT: Many alternatives have been studied on the use of agricultural, agroindustrial and forest residues in the production of particleboard in an attempt to take advantage of the residues from these branches, which often generate environmental problems due to their incorrect destination. Thus, the objective of this work was to evaluate the potential of the waste generated during the pulp production process (UKP) in the manufacture of MDP panels. The proportions used for the replacement of Pinus oocarpa wood by the residue were 0, 15, 30, 45 and 60% (by mass), using the urea-formaldehyde binder. The apparent density (DA), water absorption after two and twenty four hours of immersion (AA2h and AA24h), thickness swelling after two and twenty four hours of immersion (IE2h and IE24h), internal LI), and modulus of elasticity (MOE) and modulus of rupture (MOR) to static bending. The use of UKP residue particles for the production of MDP panels proved to be detrimental since it resulted in a decrease in mechanical properties and an increase in water absorption values and thickness swelling.

Utilization of nanotalc modified adhesives in plywood panels

“…The higher value is considered ideal, because the lignin contributes to the adhesion mechanisms and may contribute to the bonding process of the panels.Regarding the ash,Santos et al (2022) have found a content of 1,20 % close to the present study. However,Andrade et al (2019) obtained a lower content of 0,20 %. High concentrations of this component can block reactive sites for adhesion, affecting the bonding quality and mechanical performance of the panel(Soares et al 2017).For holocellulose,Mendes et al (2014) indicates that Pinus species present a content between 50 % to 85 %, thus the value obtained in this study corresponds to the stipulated range.…”

Using miriti petiole to produce particleboards

“…reported 20.15% for rice husk and 19.15% for palm trunk. The highest percentage of lignin in miriti is considered satisfactory, as it contributes to adhesion mechanisms and favors the particle bonding process(BUFALINO et al, 2012).Regarding the ash content,Andrade et al (2019a) studied the pinewood and found an average content of 0.20% lower than the respective study. For agricultural residues,Protásio et al (2012) showed higher levels for coffee residues (4.92%) and rice husks (16.78%).…”