Application of lignosulfonates combined with various urea-formaldehyde resins

This paper outlines the results obtained through testing of mixtures of adhesives based on various laboratory prepared urea-formaldehyde resins as well as on commercial UF resins and on different types of lignosulfonates. It has been established that the resins having high molar ratio of formaldehyde - urea and with low viscosity are suitable for preparing adhesives possessing good properties. Practical gluing tests have proved that by substitution of commercial resins with 200/o, of lignosulfonates can be obtained adhesives which meet the JUS standards requirements referring to plywood and particle boards.