LOW FORMALDEHYDE EMISSION UREA-FORMALDEHYDE RESINS CONTAINING A MELAMINE ADDITIVE

摘要

TITLE OF THE INVENTION:Low Formaldehyde Emission Urea-Formaldehyde Resins Containing aMelamine AdditiveABSTRACT OF THE DISCLOSURE:A melamine-urea-formaldehyde resin characterized by a low-rate of formaldehyde emission when cured. Made by a processwhere the initial reaction mixture has an F/U molar ratio of fromabout 3:1 to about 1:1, and undergoes a methylolation reaction atan alkaline pH. Preferably at least some of the melamine ispresent in the initial reaction mixture. The subsequentcondensation is at a substantially neutral pH. Has a final F/Umolar ratio of 1.3:1 to 0.9:1, a final F/Ueq molar ratio of 1.3:1 to0.7:1, and a melamine content of from 0.15% to 40% by weight, drysolids basis. Useful for adhesive purposes, particularly as aparticleboard binder characterized by low emission rate.