METHOD OF PREPARING CARBAMIDOFORMALDEHYDE OLIGOMER AND RESINS BASED THEREON Russian patent published in 2001 - IPC

FIELD: chemical industry, more particularly preparation of carbamidoformaldehyde for synthesis of adhesive resins and paintwork materials. SUBSTANCE: method is used for producing resins and other products based on carbamide and said method makes it possible to use various compositions with respect to concentration of carbamide and formalin. Also described is method of preparing carbamidoformaldehyde oligomer by mixing and condensation of formaldehyde in the form of methanol-containing formalin and carbamide followed by cooling of the resulting product. Process of condensation of carbamide with formaldehyde is carried out at initial carbamide to formaldehyde molar ratio of 1:2.8-5.6 with addition directly to formalin prior to preparing reaction mixture or to reaction mixture of carbamide and ethylene glycol or glycerol formalin in amount of 0.009-0.01 mole per 1 mole of formaldehyde followed by concentration at temperatures from 20 to 105 C up to 60- 75% of oligomer content. EFFECT: reduced toxicity of the desired products. 2 cl, 4 tbl