反应详情

温度

85 °C

Into an agitator equipped first (feed) reactor containing 68.6 grams of deionized water (D.I.) and 6.67 grams of sodium lauryl sulfate (30% active in water wt./wt.), 130.4 grams of ethyl acrylate and 69 grams of methacrylic acid are added under nitrogen atmosphere and mixed at 500 rpm to form a monomer emulsion. To an agitator equipped second reactor are added 1,340 grams of deionized water and 3.17 grams of sodium lauryl sulfate (30% active in water wt./wt.). The contents of the second reactor are heated with mixing agitation (200 rpm) under a nitrogen atmosphere. When the contents of the second reactor reaches a temperature of approximately 84° C., 27.0 grams of ammonium persulfate solution (2.0% aqueous solution wt./wt.) is injected into the heated surfactant solution. The monomer emulsion from the feed reactor is gradually metered (9.37 g/min.) into the second reactor over a period of about 30 minutes at a reaction temperature maintained at approximately 85° C. and allowed to react in a first stage polymerization reaction to form linear core polymer particles of ethyl acrylate/methacrylic acid copolymer. Following the initial addition of the monomer emulsion into the second reactor, the second stage monomer emulsion is prepared in the feed reactor by adding 274.4 grams of deionized water (D.I), 26.67 grams of sodium lauryl sulfate (30% active in water wt./wt.), 521 grams of ethyl acrylate, 276 grams of methacrylic acid, and 3.0 grams of trimethylolpropane triacrylate. The monomer emulsion containing the added trimethylolpropane triacrylate is then metered into the second reactor over a period of 120 minutes at a controlled rate (7.5 g/min.) at a temperature maintained at approximately 85° C. and polymerized in the presence of the linear core polymer particles in a second stage reaction to form a crosslinked polymer shell (over the core polymer particles) comprising polymerized ethyl acrylate/methacrylic acid/trimethylolpropane triacrylate copolymer. With the emulsion monomer feed, 60 grams of ammonium persulfate (0.37% aqueous solution wt./wt.) is simultaneously metered into the reaction mixture in the second reactor and the temperature of the reaction is maintained at about 85° C. for an additional two and half hours to complete polymerization. The resulting polymer emulsion product is cooled to room temperature, discharged from the reactor and recovered. The core and shell monomer components are set forth in Tables 1 and 1A, respectively, and the polymer stage compositional information is presented in Table 1C.

1. customInto an agitator equipped first (feed) reactor
2. additionare added under nitrogen atmosphere
3. additionmixed at 500 rpm
4. customto form a monomer emulsion
5. customTo an agitator equipped second reactor
6. temperatureThe contents of the second reactor are heated
7. additionwith mixing agitation (200 rpm) under a nitrogen atmosphere
8. customof about 30 minutes
9. customto react in a first stage polymerization reaction