ADHESIVES BASED ON UREA-FORMALDEHYDE RESINS AND LIGNOCELLULOSIC WASTE

Abstract

In order to develop a sustainable economy and due to increasing economic and environmental issues concerning the use of petrochemicals, lignocellulosic materials, as natural, abundant and renewable resources, will be extensively used in the future, as raw materials, for the production of chemicals, fuels and composite materials. Our research has been focused on synthesis and characterization of some new, ecological composite adhesives based on woody wastes fillers ammonium, calcium and iron lignosulfonates and Salix wood aqueous extract, as partial substituents for toxic, synthetic monomers urea and formaldehyde in the synthesis of urea-formaldehyde adhesives (matrix). The improvements achieved, by using the lignosulfonates and Salix wood extract, in the properties of the new composite adhesives urea-formaldehyde-lignosulfonate-Salix extract consist on decreasing of the gel time and the content on free formaldehyde, increasing the water resistance, the pot life, the resistance to biodegradation and low costs.