SU96335A1 - The method of obtaining dry resole resins from technical xylenols - Google Patents

Description

Applying the first commonly used methods of condensing technical xllenols leads to the formation of low-quality resins with low viscosity and low dropping point. Only the addition of significant quantities of crystalline phenol to the technical xylenol (60 parts by weight to 40 parts by weight of xylenol) gives acceptable resin properties.

Changing the formulation and condensation of the proposed method allows to obtain a press material of good quality with simultaneous significant reduction; consumption of crystalline phenol.

The method consists in the use of an alkaline catalyst followed by neutralization. Condensation with an alkaline catalyst occurs at a temperature of 65-80 to reach a viscosity of 400-700 centipoise, after which the alkaline catalyst is not neutralized with phosphoric acid, fatty acids and resin are introduced and dried. At the end of the drying, 50 o-hpp water solution of urotroHiiHa is introduced into the boiler in the amount of 2.5 weight. h

Example. In the boiler, 5 lg load 70 weight. including xylenol, 30 wt. including phenol. 40 wt. including formaldehyde, 0.9 weight. including magnesium and 0.3 wt. including 100% caustic natrn. The mixture is not quenched for 0 minutes, after which steam is supplied to the jacket under a pressure of 0.2-0.5 ° T.i; and the reaction mixture is heated to. The steam is then turned off, and further heating of the reaction mixture occurs due to the exothermic reaction. At 60 k, a refrigerator of the apparatus is given complete cooling and the stirrer is turned off. At 85, boiling begins. In 5-7 minutes the mixture is cooled to 80. Farther condensation is carried out at 75-80 ° until the viscosity of the resin at Ostwald reaches 200 centipoise. The temperature drops to 65, and the mixture

No. 96335-2 -

is maintained at a temperature of 65-75 to a viscosity of 400-700 centipoise. Then the alkaline catalyst is neutralized with 25% phosphoric acid solution (, 7 weight parts per 100% acid). After 5

7mip. mixing, the fatty acids in the amount of Zves are introduced. h

8 course 5 min. mixing with acids is carried out, and the resin is transferred to drying under a vacuum of 500 mm. After the main mass of water is distilled off, a 50% aqueous solution of urotropin is introduced into the boiler. The resin is dried in the usual way and drained into refrigerated cars.

Subject invention

The method of obtaining dry resole resins from technical xylenols with the addition of 30% crystalline phenol and 2.5% hexamine during the drying process, characterized in that the condensation is carried out at 65-80 with an alkaline catalyst to a resin viscosity of 400-700 centipoise, after which the alkali is neutralized phosphoric acid and dried resin in the usual way.