METHOD OF PRODUCTION OF THE CARBAMIDE-FORMALDEHYDE RESIN Russian patent published in 2006 - IPC C08G12/12 

FIELD: chemical industry; construction materials industry; methods of production of the carbamide-formaldehyde resin.

SUBSTANCE: the invention is pertaining to the methods of production of the water soluble carbamide-formaldehyde resins applied as binding agents and adhesives used for the timber bonding in production of the wood chipboards, the wood-fiber boards, other similar materials and the heat-insulating materials. The method of production of carbamide-formaldehyde resin provides for condensation of the amino-formaldehyde concentrate representing the aqueous composition, containing of 41.5-60.0 mass % of the formaldehyde and of 20.5-25.0 mass % of the carbamide with the viscosity controller , I the capacity of which use 37 % formalin introduced in one step together with the carbamide-formaldehyde concentrate at the stage of the alkaline condensation before the loading of the first batch of the carbamide and also at presence of 0.02-0.20 mass % of the first batch of the of the additive agent in terms of 100 mass % of the carbamide-formaldehyde concentrate and the first batch of carbamide at the heating in the water solution with the variable acidity and the following additional condensation of the formed product with the additional amount of carbamide and introduction of the second batch of the buffer additive component at the initial and the final molar ratio of carbamide and formaldehyde as 1:(1.9-2.1) and 1:(1.02-1.7) accordingly and the refrigerations of the ready resin. The technical result of the invention is optimization of the conditions for production of the low-molar carbamide-formaldehyde resins with the heightened conditional viscosity and preservation at the high level of the other quality factors.

EFFECT: the invention ensures optimization of the conditions for production of the low-molar carbamide-formaldehyde resins with the heightened conditional viscosity and preservation at the high level of the other quality factors.

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