Enhancing environmental performance of formaldehyde-based adhesives in lignocellulosic composites

The aim of this work is to produce less toxic lignocellulosic composites from agricultural wastes such as sugar-cane bagasse by using conventional urea-formaldehyde adhesives. Two approaches were studied: the first focused on using certain inorganic ammonium salts as accelerators for cross-linking of the formaldehyde-based adhesive, while the second focused on using organic additives capable of scavenging free formaldehyde. The effect of these additives on the percentage of free formaldehyde in adhesive system and the adhesion properties (physical and mechanical properties) of the composites produced were examined. The concentration and type of additives used to achieve high board properties were optimized. The behavior of the additives as fire retardants also was examined by using thermogravimetric analysis. The thermal degradation behavior of some of the composites has been studied by means of nonisothermal thermogravimetric analysis, and the kinetic parameters were estimated.