Utilização de lignosulfonato e adesivo Fenol-Formaldeído na produção de painéis aglomerados

Abstract

The purpose of this study was to evaluate the feasibility of using calcium and magnesium lignosulfonate (LS) in the production of Pinus caribaea var. caribaea particleboard panels, used pure and in mixtures with phenol-formaldehyde (FF). In order to evaluate the effect of FF replaced by LS on the physical and mechanical properties, panels were produced with different concentrations of these adhesives. The experiment consisted of two phases: The first phase was performed under temperature of 160°C and pressing time of 10 minutes with the following compositions: 100% FF, and LS substitutions in the proportions of 20, 40, 60, 80 and 100%, with three replications each. In the second phase, the first phases of the three treatments with lower performance in the mechanical properties were tested at a temperature of 180°C and up to 7 minutes. The results of basic and apparent wood density were 0.54 and 0.60 g/cm3, respectively. In the second stage, the temperature increase and decrease of the pressing time were not sufficient to consolidate the panel, rendering the analysis of the results of this phase not possible. As for thickness swelling and water absorption, increases in the proportion of lignosulfonate in the mixture also raised up those values. The replacement of the phenolformaldehyde adhesive by lignosulfonate was satisfactory, attending the specific norm for mechanical properties by 80%. Lignosulfonate showed efficiency as use as an adhesive in the production of particleboard in mixtures with phenol formaldehyde, suggesting that this is an alternative to the use of synthetic adhesives.