METHOD FOR PREPARING CARBAMIDE-PHENOL-FORMALDEHYDE-FURAN BINDING AGENT FOR CASTING SHELL FORMS AND RODS Russian patent published in 2007 - IPC B22C1/22 

FIELD: casting manufacture.

SUBSTANCE: invention relates to methods for preparing binding agents for casting shell forms and rods being both for cold-hardening and hardening articles in the hot equipment. Method involves the condensation reaction of monomers of carbamide, furfuryl alcohol, phenol and formaldehyde wherein carbamide-formaldehyde concentrate is used as formaldehyde-containing and carbamide-containing components. The condensation reaction is carried out successively into a single reactor and with absence of vacuum-drying wherein carbamide-formaldehyde concentrate is heated firstly at pH 8.0-8.5 and then at pH 5.0-5.5. Then phenol is added to a synthesized oligomer and the condensation reaction is carried out at pH 8.0-8.5 followed by addition of furfuryl alcohol and carrying out the further condensation process. Method provides carrying out the ecologically pure manufacturing and enhancing quality of a binding agent.

EFFECT: improved method of synthesis.

4 cl, 4 tbl, 1 ex