| 摘要 |
FIELD: method for production of impregnating melamine-carbamide-formaldehyde resins useful in paper-tar films for lamination of particle boards and plywood. ^ SUBSTANCE: claimed method includes condensation of carbamide-formaldehyde concentrate with melamine or carbamide or mixture thereof in presence of 0.2-1.8 mass % of amine modifier as calculated to 100 mass % of formaldehyde-containing product, introduced in two steps up to final molar ratio of formaldehyde: melamine:carbamide = (1.83-2.0):(0.10-0.70):(0.33-1.20), total melamine dissolution, and resin cooling. As formaldehyde-containing product carbamide-formaldehyde concentrate comprising (mass %): carbamide 20-25; formaldehyde 55-60; and balance: water is used. Said product is obtained by methanol oxidative dehydration on iron-molybdenum catalyst in tube reactor followed by chemosorption of formaldehyde-containing gas with carbamide solution; and as amine modifier product containing (mass %) monoethanole amine 15-70; mixture 1-(2-oxyethyl)imidazolidone-2 and 1-(2-oxyethyl)ethylenediamine not more than 50; and balance: water. ^ EFFECT: optimized synthesis method; resin of improved quality, namely increased viscosity and decreased methanol content. ^ 3 ex, 1 tbl |
