FORFARANDE FOR FRAMSTELLNING AV ALKYLRESORCINOLFENOL-FORMALDEHYDHARTS

摘要

The process comprises reacting the phenol with formaldehyde in the presence of an alkali metal catalyst in an aqueous solution at a temperature of from 60 to 70 DEG C for from 4 to 8 hours with subsequent polycondensation in an aqueous ethanol solution with addition of a fraction of shale alkylresorcinols having a boiling point of 270-290 DEG C in a ratio between the components, in per cent by weight, of phenol:formaldehyde:alkylresorcinol fraction:ethanol:water of 1:0.41-0.67:1.55-2.3:0.3-1:0.8-1.5. The polycondensation can be carried out with addition of 0.3-0.6 part by weight of ethylene glycol. The temperature of the polycondensation is kept at the boiling point of from 93 to 98 DEG C for 2.5-6 hours.