Reaction #2275723

Reaction equation

formaldehyde

DBU

naphthalenesulfonic acid

DBU

→

DBU

naphthalenesulfonic acid formalin

Solvents

water

water

Conditions

Workup

1. 1
   OtherTo a reaction vessel equipped with a stirrer
2. 2
   workup.ADDITIONAfter completion of the dropwise addition
3. 3
   Temperaturethe reaction mixture was heated to 105 C

Procedure

To a reaction vessel equipped with a stirrer and temperature controller were added 21 parts of naphthalenesulfonic acid and 10 parts of ultrapure water. While keeping the temperature of the system at 80 C under stirring, 8 parts of 37% formaldehyde was added dropwise over 3 hours. After completion of the dropwise addition, the reaction mixture was heated to 105 C and the reaction was continued for 25 hours. Thereafter, the reaction mixture was cooled to room temperature (ca. 25 C) and, while keeping the temperature at 25 C in a water bath, DBU was added gradually to adjust the pH to 6.5 (ca. 15 parts of DBU was used). The solid content was adjusted to 40% by addition of ultrapure water to thereby obtain a 40% aqueous solution of a DBU salt of naphthalenesulfonic acid-formalin condensate (B-2), a polymeric anionic surfactant. In addition, the Mw of (B-2) was 5,000.

Source