Formaldehyde Abatement of Particleboard Sustrate with Several Scavenger Resins, 1996 Plastic Laminates Symposium Proceedings

The formaldehyde scavenging effects and particleboard physical properties of an analogous series of formaldehyde scavengers, comprised of an urea-formaldehyde (UF) scavenger resin with higher degree of condensation, an UF scavenger resin with low degree of con-densation and an urea solution (40%), and of a melamine-urea-formaldehyde (MUF) scavenger resin, were examined by laboratory made particlebaords. These laboratory particleboards were made by mixing each scavenger with the primary UF binder to the final combined mole ratios of 1.05, 1.15 and 1.25 (unscavenged) immediately before par-ticleboard manufacturing. The analogous series of scavengers, as well as the MUF scavenger resin, were found to lower the formaldehyde emis-sion of particlebaords by 70%. Strength properties of particleboards made with the analogous series of scavengers were found to depend on the degree of con-densation of the scavenger, with higher degree of condensation giving better strength properties, and urea solution approaching the properties of the un-scavenged boards. The MUF scavenged boards show slightly inferior strength properties. No difference was observed on thickness swell and water absorption properties among the scavengers tested, when compared to the control boards. Formaldehyde emission of the particle-boards tested showed a decreasing trend as the combined final mole ratio of the binder/scavenger mixes decreased, with the 1.05 combined final mole ratio boards averaging 76% less than the un-scavenged (1.25 mole ratio) boards. Particleboard strength properties also showed a decreasing trend as the com-bined final mole ratio decreased. No mole ratio dependence was observed with thickness swell and water absorp-tion properties.