Continuous Structural Evolution of Calcium Carbonate Particles: A Unifying Model of Copolymer-Mediated Crystallization
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- 作者：Alex N. Kulak ; Peter Iddon ; Yuting Li ; Steven P. Armes ; Helmut Cö ; lfen ; Oskar Paris ; Rory M. Wilson ; Fiona C. Meldrum
- 刊名：Journal of the American Chemical Society
- 出版年：2007
- 出版时间：March 28, 2007
- 年：2007
- 卷：129
- 期：12
- 页码：3729 - 3736
- 全文大小：554K
- 年卷期：v.129,no.12(March 28, 2007)
- ISSN：1520-5126
文摘
Two double-hydrophilic block copolymers, each comprising a nonionic block and an anionic blockcomprising pendent aromatic sulfonate groups, were used as additives to modify the crystallization of CaCO3.Marked morphological changes in the CaCO3 particles were observed depending on the reaction conditionsused. A poly(ethylene oxide)-b-poly(sodium 4-styrenesulfonate) diblock copolymer was particularly versatilein effecting a morphological change in calcite particles, and a continuous structural transition in the productparticles from polycrystalline to mesocrystal to single crystal was observed with variation in the calciumconcentration. The existence of this structural sequence provides unique insight into the mechanism ofpolymer-mediated crystallization. We propose that it reflects continuity in the crystallization mechanismitself, spanning the limits from nonoriented aggregation of nanoparticles to classical ion-by-ion growth.The various pathways to polycrystalline, mesocrystal, and single-crystal particles, which had previouslybeen considered to be distinct, therefore all form part of a unifying crystallization framework based on theaggregation of precursor subunits.