Microspheres of calcium carbonate composite regulated by sodium polyacrylates with various ways

Abstract

Microspheres of calcium carbonate (CaCO3)/ sodium polyacrylate (PAAs)/H2O composite were synthesized by adding PAAs to the supersaturated solution of CaCO3. It was found that the sizes of microsphere were influenced by the concentration and average molecular weight (Mw) of PAAs. Particularly, the polymorph of CaCO3 in the microspheres could be regulated by Mw of PAAs, that is, the formation of aragonite was induced by PAAs with lower Mw, while the amorphous calcium carbonate (ACC) was facilitated by PAAs with a higher one. Both polymorphs in produced microspheres were stable in air for longer than 3 months. In addition, it was revealed that the formation of calcite crystals was suppressed by a highly concentrated solution of PAAs. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 3686-3692, 2009.