Manufacturing method of melamine-urea-formaldehyde resin adhesive for medium density fiberboards

摘要

PURPOSE: A manufacturing method of a melamine-urea-formaldehyde resin adhesive is provided to reduce the manufacturing method of the adhesive by simplifying the synthesizing process of the adhesive. CONSTITUTION: A manufacturing method of a melamine-urea-formaldehyde resin adhesive for a medium-density fiberboard comprises the following steps: controlling the pH of formaldehyde into 8.8~9.2 by adding an alkaline catalyst and the reaction temperature into 70~80 deg C, adding 120~198 parts of melanin by weight, increasing the reaction temperature into 88~92 deg C and maintaining the temperature; controlling the molar ratio of the formaldehyde/element in to 1.50~1.64, and performing a condensation reaction and collecting non-reactive formaldehyde; and maintaining the pH into 8.3~8.7 by adding the alkali catalyst or an acid catalyst.