METHOD OF PREPARING RESORCINOL-FORMALDEHYDE RESIN Russian patent published in 2001 - IPC

FIELD: tire and rubber-processing industries, more particularly component of aqueous adhesive for fixing textile materials to rubber during vulcanization process. SUBSTANCE: describes is method of preparing resorcinol-formaldehyde resin by polycondensation of resorcinol and formaldehyde in monohydric alcohol and ethylene glycol. Method comprises precondensation at 40-45 C and further maintenance of reaction mixture at boiling temperature followed by addition of sodium hydroxide to adjust pH at 7.5-8.5. Monohydric alcohol is butanol, precondensation is carried out at above-indicated temperature for 1.65-2.5 hours, reaction mixture is then heated to 50-55 C at temperature rise rate of 1-2 C/min and maintained at boiling temperature to attain viscosity of 30-60s as measured by viscosimeter. Five hazard of method is thus reduced, and range of manufacture resorcinol- formaldehyde resins is made wider. Resin has high adhesion properties, thus attaining high strength of bond of rubbers with textile materials. EFFECT: more efficient preparation method. 4 ex, 1 tbl