Modified urea-formaldehyde resin adhesive for concrete formwork and production method of adhesive

The invention discloses a modified urea-formaldehyde resin adhesive for a concrete formwork, which is mainly prepared from the following raw materials in parts by weight: 50 to 60 parts of formaldehyde with the mass concentration of 37 percent, 20 to 30 parts of urea with purity of 98 percent, 6 to 8 parts of melamine, 0.1 to 0.2 part of tackifier and 0.2 to 0.3 part of accelerant. The adhesive has an Uron-ring improved structure, so that the waterproofness of the formwork can be improved. The invention also discloses a production method of the adhesive, which comprises three steps of strong acid, weak acid and weak base. The reaction between the formaldehyde and the urea under a strong acid reaction condition can be effectively controlled by controlling temperature, pH value, charging speed, charging time and molar ratio. Meanwhile, two endpoint control indexes which are simple and convenient and are easy to operate are provided, and therefore processing implementing can be controlled conveniently and accurately.