Formaldehyde → Formaldehyde;phenol

Temperature

80 °C

Phenol ( 1 mol) and 50% formalin (0.6 mol) were charged to a reaction vessel and the temperature maintained below 40° C. whilst sodium hydroxide (0.004 mol) was added. The temperature was then raised to 80° C. The temperature was maintained at 80° C. while a second charge of 50% formalin (1.0 mol) was added slowly over 30 minutes and the temperature maintained at 80° C. for a further 15 minutes. The mixture was then held at 70° C. for a further 30 minutes. The pH was adjusted with p-toluene sulphonic acid solution to 4.0 +/-0.2 and the volatiles distilled off under vacuum at 70° C. to a viscosity of 80 centistokes at 25° C. The resin was cooled to 60° C., the pH adjusted to 6.2 +/-0.02 with sodium hydroxide, 0.027 moles of urea were added and the product further concentrated to a final viscosity of 500 cP at 25° C., cooled and discharged.

1. additionwas added
2. temperatureThe temperature was maintained at 80° C. while
3. additionwas added slowly over 30 minutes
4. temperaturethe temperature maintained at 80° C. for a further 15 minutes
5. distillationthe volatiles distilled off under vacuum at 70° C. to a viscosity of 80 centistokes at 25° C
6. temperatureThe resin was cooled to 60° C.
7. additionwere added
8. concentrationthe product further concentrated to a final viscosity of 500 cP at 25° C.
9. temperaturecooled

ORD record

ord-492bec93932549deadc5497694d25ccc

Source dataset

uspto-grants-1991_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05051454