Mechanical properties of accelerated aging particleboards

Abstract

The aim of this work was to evaluate the mechanical properties of particleboards before and after accelerated artificial aging. Particleboards were produced using wastes of Eucalyptus grandis wood and oat hulls (Avena sativa), glued with polyurethane adhesive based on castor oil. The mechanical properties modulus of elasticity (MOE) and modulus of rupture (MOR) were evaluated through ANSI A208.1: 1999 and BS EN 312: 2003. In the experimental design, the following experimental conditions were adopted: mass ratios of particles of Eucalyptus grandis wastes and oat hulls (100/0, 85/15, 70/30 and 0/100, respectively), and mass proportions of adhesive (10, 12 and 14%), generating 12 treatments. Six panels were produced per treatment, totaling 72 particleboards. An analysis of variance (ANOVA) was performed to evaluate if the factors and levels adopted in the experimental design influenced the mechanical properties evaluated. The accelerated artificial aging tests followed APA D-1 Cycle, from the APA PRP 108: 1994 standard. The results showed, in several treatments, the properties followed the standards' requirements, being superior to them in some treatments. After aging, only one treatment (for MOE) and three treatments (for MOR) met the requirements of at least one of the standards. It was concluded that the accelerated artificial aging (APA D-1 cycle) is the least aggressive cycle of the APA PRP 108 standard. Even so, it destroyed some of the panels and reduced density and MOE and MOR properties.

Variação das propriedades tecnológicas de painéis MDF em uma linha de produção industrial no Brasil

“…Ressalta-se que o tratamento de envelhecimento artificial acelerado em painéis derivados de madeira avalia a influência de condições controladas de fatores de degradação, como o calor e umidade no desempenho tecnológico, permitindo a estimação da durabilidade e comportamento dos painéis ao longo do tempo por meio das mudanças em suas propriedades Research, Society and Development, v. 10, n. 11, e478101119951, 2021 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v10i11.19951 físico-mecânicas (Garzón et al, 2012;Varanda et al, 2019). O tratamento de envelhecimento artificial promoveu diminuição expressiva no desempenho dos painéis MDF de ambos os horários avaliados, em que, após o envelhecimento todas as propriedades não atenderam aos valores previstos na norma (Tabela 1).…”