Preparation method of E0-grade melamine modified urea-formaldehyde resin

The invention discloses a preparation method of E0-grade melamine modified urea-formaldehyde resin, and relates to the technical field of urea-formaldehyde resin production. Main raw materials comprise formaldehyde, urea, melamine, starch slurry and activated carbon. The urea is divided into two batches and is respectively added when the urea is neutral and acidic, the molar ratio of the first batch of urea to the formaldehyde is (0.5-0.6): 1, the molar ratio of the second batch of urea to the formaldehyde is (0.4-0.5): 1, the melamine is respectively added at the initial stage of reaction and the addition stage, the use amount of the melamine is respectively 3% and 7% of the use amount of the urea, and the starch slurry is added before the reaction; the activated carbon is added at the later stage of the reaction and sequentially passes through a neutral medium, an acidic medium and an alkaline medium, and finally the E0-grade melamine modified urea-formaldehyde resin is prepared. The melamine modified urea-