Efeito da associação de bagaço de cana, do tipo e do teor de adesivo na produção de painéis aglomerados.

Abstract

RESUMOEste trabalho teve como objetivo avaliar o efeito da associação de bagaço de cana, tipo e teor de adesivo nas propriedades físico-mecânicas de painéis aglomerados com madeira de Pinus spp. O delineamento experimental se constituiu de um esquema fatorial 3x2x3, sendo três porcentagens de substituição de madeira de pinus por bagaço de cana -25, 50 e 75%; dois tipos de adesivos -fenol-formaldeído (FF) e ureia-formaldeído (UF); e três teores de adesivo -6, 9 e 12%. O ciclo de prensagem utilizado foi de pressão de 40 kgf/cm², temperatura de 160ºC para UF e de 180ºC para FF, e por um tempo de 8 minutos. Mediante os resultados pode-se concluir que: 1) Para a porcentagem de associação de bagaço de cana, nas propriedades em que foi observado efeito significativo, a tendência foi de diminuição da qualidade dos painéis à medida que se aumenta a quantidade de associação de bagaço de cana; 2) O adesivo UF se mostrou estatisticamente igual ou superior a FF em todas as propriedades avaliadas; 3) Os teores de adesivo apresentaram efeito significativo para todas as propriedades analisadas, sendo que, com exceção da propriedade ligação interna, em todas as outras propriedades o teor de 12% foi estatisticamente superior a 6%, e ainda igual ou superior a 9%. Palavras-chave: aglomerados; bagaço de cana; pinus; tipo e teores de adesivo. ABSTRACTThis study aimed to evaluate the association effect of sugar cane bagasse, type and levels of adhesive in the physical-mechanical properties of particleboards with Pinus spp. wood. The experimental design consisted of a 3x2x3 factorial scheme, with three percentages of substitution pine wood by sugar cane bagasse -25, 50 and 75%; two types of adhesives -phenol-formaldehyde (PF) and urea-formaldehyde (UF); and three levels of adhesive -6, 9 and 12%. The cycle of pressing used was 40kgf/cm² pressure, temperature of 160ºC for UF and 180ºC for PF, and for a time of 8 minutes. From the results, it is concluded that: 1) For the percentage of sugar cane bagasse association, in the properties where significant effect was observed, the trend was decrease in panel quality as the amount of sugar cane bagasse increases; 2) The UF adhesive was statistically equal or greater than PF in all evaluated properties; 3) The levels of adhesive showed significant effects for all properties; Except for internal bond property, in all other properties the level of 12% was statistically superior to 6%, and equal or greater than 9%.

Effect of Post-production Heat Treatment on Particleboard from Sugarcane Bagasse

“…With regard to the IB property, only the control treatment met the requirements of the standard. These low IB values, regardless of the heat treatment, have also been observed in several studies on bagasse panels 3,9,10 , which is basically owing to the low density of the bagasse material and the consequent need to increase the number of particles to form a panel of predetermined density. This causes an increase in the surface area for the same amount of adhesive, thus more markedly promoting the decrease in the IB property.…”

“…Mendes et al 3 evaluated the production of particleboard from bagasse in association with pine wood and the adhesive urea-formaldehyde and obtained WA2h values ranging from 32.1% to 54.1% and WA24h values ranging from 49.8% to 64.2%. Furthermore, Mendes et al 10 evaluated different types of agricultural and forest residues for particleboard manufacturing and observed WA24h and WA2h values of 12.6% and 60.6%, respectively, for the panels produced with cane bagasse.…”

“…However, in principle, these panels can be produced from any lignocellulosic material that provides high mechanical strength and good physical characteristics 1,2,3 . Thus, the recovery of waste generated by the Brazilian agribusiness industry has become an alternative to meet the demand of the particleboard industry, which is exhibiting increased growth.…”

“…The Brazilian agroindustry offers many types of lignocellulosic residues, which have potential for particleboards production such as corncob, rice husk, coffee hull, peanut hull, banana plant stem, coconut husk, cassava stem, castor bean hull, sugarcane bagasse, etc. 3,4 . Among the agricultural waste, sugarcane bagasse stands out because Brazil is a world leader in the production of sugarcane, with a production of approximately 1.8 billion tons in 2011 5 , which represents the generation of about 500 million tons of sugarcane bagasse, because, according to Silva et al 6 , each ton of processed cane sugar generates a total of 280 kg of waste.…”

Use of maize cob for production of particleboard

“…Mendes et al (2012) evaluated particleboard panels produced with sugarcane bagasse associated to pinewood (25, 50 and 75%) and found MOE values ranging from 810 to 823 MPa, and MOR values ranging from 9.3 to 11 MPa.…”