METHOD FOR PRODUCING LIGNOPHENOL-FORMALDEHYDE RESIN Russian patent published in 2024 - IPC C08F2/04 C08G14/04 C08G8/28 

FIELD: chemistry.

SUBSTANCE: method for producing a modified phenol-formaldehyde resin of the resol type. A method has been proposed for producing lignophenol-formaldehyde resin by interacting a ligno-containing component, which is a product of technological processing of plant raw materials at pulp and paper mills, being salts of lignosulfonic acids, which are natural water-soluble sulphonate derivatives of lignin, with a solution of hydrogen peroxide at 30-80 °C, followed by introduction of formaldehyde into the reaction system, condensation in the presence of solutions of inorganic acids as catalysts, neutralization with alkali to pH 7-8, addition of phenol and water, after which alkaline condensation is carried out, holding and cooling the system, while the molar ratio of phenol and formaldehyde is 1:2.4-1:3.0.

EFFECT: expansion of the raw material base for the synthesis of phenol-formaldehyde resins, improved performance of lignoformaldehyde resin.

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