反应详情

温度

60 °C

An aqueous mixture of 751 g deionized water, 101 g Ludox SM-30 (a colloidal silica dispersion, available from E.I. duPont de Nemours & Co.), and 5.5 g of a 50% solution of diethanol-adipic acid condensate (as promoter) was stirred in a glass jar and the mixture was adjusted to a pH of 4 by addition of 10% sulfuric acid. A monomer solution of 88.4 g caprolactone acrylate obtained from Sartomer Co. (Exton, Pa.), 354 g 1,6-hexandiol diacrylate, and 2.1 g VAZO 64 initiator (2,2'-azobis(isobutyronitrile)), available from E.I. duPont de Nemours & Co. was prepared separately. The aqueous mixture and the monomer solution were poured into a 5-liter split resin flask equipped with a marine-propeller type stirrer and mixed at about 1500 rpm (revolutions per minute) for 2 minutes. The mixture was then poured out of the flask and passed through a Manton-Gaulin Homogenizer available from the APV Gaulin Inc. (Everett, Mass.) at 700-900 psi (pounds per square inch, 4.8×106 -6.2×106Pascals) three times. The homogenized suspension was returned to the resin flask. The content was heated with infrared lamps to 60° C. under a nitrogen blanket and agitated at about 500 rpm (revolutions per minute) for 15 hours. A stable suspension of polymer particles was obtained. Analysis with Coulter N4 submicron particle size analyzer, available from Coulter Electronic Inc. (Hinleah, Fla.) showed an average particle size of 1.1 microns. The suspension was filtered with Whatmann #54 filter paper on a 24-cm Buchner funnel and washed several times with deionized water to give a wet cake. The wet cake was placed on glass trays and dried at ambient condition for several days. The dry cake was put in a gallon glass jar along with glass marbles and placed on a roller for several days to give free-flowing powder (average particle size=1.1 microns).

1. additionAn aqueous mixture of 751 g
2. customwas prepared separately
3. additionThe aqueous mixture and the monomer solution were poured into a 5-liter
4. customsplit resin flask
5. customequipped with a marine-propeller type stirrer
6. additionmixed at about 1500 rpm (revolutions per minute) for 2 minutes
7. additionThe mixture was then poured out of the flask
8. additionA stable suspension of polymer particles
9. customwas obtained
10. filtrationThe suspension was filtered with Whatmann #54
11. filtrationfilter paper on a 24-cm Buchner funnel
12. washwashed several times with deionized water
13. customto give a wet cake
14. customdried at ambient condition for several days
15. waitplaced on a roller for several days
16. customto give free-flowing powder (average particle size=1.1 microns)