Formaldehyde → Melamine formaldehyde

Temperature

90 °C

Specifically, melamine is added to an aqueous solution of formaldehyde having a pH adjusted to 8 to 9; while being maintained at a temperature of60° to 90° C., the obtained mixture is stirred to conduct dissolution and a reaction; at the point of time at which the solution hasbecome cloudy, the mixture is cooled in a suitable time to stop the condensation; the resulting mixture is dried by spraying or the like to give crude melamine-formaldehyde polycondensate as a powder; this crude melamine-formaldehyde polycondensate is washed with warm water (50°to 70° C.) for 30 minutes to one hour and filtered; the residue was dissolved in dimethyl sulfoxide and insoluble solids are removed by filtration; the filtrate is added to a large excess of acetone to form precipitates, which are recovered by filtration and dried; thus, pure melamine-formaldehyde polycondensate can be obtained as a white powder.

1. dissolutiondissolution
2. customa reaction
3. temperaturethe mixture is cooled in a suitable time
4. customthe condensation
5. customthe resulting mixture is dried
6. customthe like to give crude melamine-formaldehyde polycondensate as a powder
7. washthis crude melamine-formaldehyde polycondensate is washed with warm water (50°to 70° C.) for 30 minutes to one hour
8. filtrationfiltered
9. dissolutionthe residue was dissolved in dimethyl sulfoxide
10. custominsoluble solids are removed by filtration
11. additionthe filtrate is added to a large excess of acetone
12. customto form
13. customprecipitates
14. filtrationwhich are recovered by filtration
15. customdried

ORD record

ord-5d3a6a17d2914692a7c4effab2bc849b

Source dataset

uspto-grants-1995_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05446086