Preparation method of modified melamine formaldehyde resin for impregnation

The invention discloses a preparation method of modified melamine formaldehyde resin for impregnation. The modified melamine formaldehyde impregnating resin is produced through acidic-condition reaction and alkaline-condition reaction in sequence, the reaction technology is simple, an aldehyde solution is added to a reaction kettle, stirring is started, melamine (M) is added, all components are sufficiently and uniformly mixed, a mixture is heated to 30-60 DEG C and subjected to a reaction for 10-60 min, then alkali liquor is added to regulate pH to 7.0-13.0, the temperature is increased to 60-100 DEG C, a modifier is added 10-60 min after the reaction solution becomes clear, a reaction is performed for 0.5-3 h, then a solid content regulating solvent is added, cooling and discharging are performed, and an impregnating adhesive is stored and blended for production.