Aqueous solutions of etherified melamine-formaldehyde resins with long shelf life and low free formaldehyde content

摘要

An etherified melamine-formaldehyde resin is disclosed that has prolonged shelf life, comparatively low free formaldehyde content, and is especially adapted as a binder for glass fiber mats. The melamine- formaldehyde resin is prepared in several distinct stages including condensation in a basic aqueous solution, etherification by cooling and acidification, neutralization with triethanolamine, and final stabilization. The free formaldehyde content of the resin so produced can be adjusted by reacting it with urea.