反应详情

Into a 5 liter 3-neck round bottom flask is charged 2960 ml of deionized (DI) water. The water is heated with a heating mantle to 85°-87° C. while being stirred with a mechanical stirrer. While this is being done, 416 g of acrylic acid (AA) and 104 g of 2-hydroxyethyl methacrylate (HEMA) are charged into a one-liter graduated separatory funnel. A 1 wt.% aqueous solution of ammonium persulfate (APS) is also prepared. When the temperature of the water levels off at 85°-87° C., 13 ml of the 1 wt.% APS solution is added to the reactor. The monomer solution and a co-feed catalyst of 52 ml of the 1 wt.% APS solution are then added gradually and proportionally to the reactor over a period of about two hours. During the addition the temperature is maintained at 85°-87° C. and agitation is increased gradually to maintain good stirring. After the additions are completed the polymer solution is held at 85°-87° C. for 30 minutes. At the end of the 30 minute time period an additional catalyst system consisting of 0.4 g of tertiary butyl hydroperoxide diluted in 10 ml of DI water and 0.3 g of sodium sulfoxylate formaldehyde dissolved in 10 ml of DI water are added. Stirring is continued for 30 minutes. A neutralizer consisting of 232 g of 50% sodium hydroxide is added. Stirring is continued for about 30 minutes. The product obtained is a clear solution with a viscosity of about 7000 cps (Brookfield Viscometer, 12 rpm, spindle 3, 20° C.±2° C.) and has a polymer solids content of 15.4% with about 50% of the acid groups neutralized.

1. additionDuring the addition the temperature
2. temperatureis maintained at 85°-87° C.
3. temperatureagitation is increased gradually
4. temperatureto maintain good stirring
5. customAt the end of the 30 minute time period
6. additionare added
7. stirringStirring
8. waitis continued for 30 minutes
9. additionis added
10. stirringStirring
11. waitis continued for about 30 minutes
12. customThe product obtained
13. customof about 7000 cps (Brookfield Viscometer, 12 rpm, spindle 3, 20° C.±2° C.)