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アモルフなCaCO3:形成時間の水分と安定度の影響
Huachuan Du1, Mathias Steinacher1, Camelia Borca2
1Soft Materials Laboratory , Institute of Materials, École Polytechnique Fédérale de Lausanne (EPFL) , 1015 Lausanne , Switzerland.
Journal of the American Chemical Society
|September 29, 2018
まとめ
研究者たちは,無形カルシウム炭酸 (ACC) の形成を研究するための新しい方法を開発しました. 大きなACC粒子は水分を多く含んで 安定性が低下しますが PAAのような添加物は 安定性を改善します
科学分野:
- 材料科学
- バイオミネラル化
- 化学工学
背景:
- カルシウム炭酸 (CaCO3) は自然に豊富に存在し,優れた機械的特性を持つ海洋構造に使用されます.
- 合成材料でこれらの性質を複製するには,CaCO3の形成を理解することが重要です.
- 現在の方法では,初期段階の無形CaCO3 (ACC) 形成を研究するための時間解像度が不足しています.
研究 の 目的:
- 初期の形成段階における無形カルシウム炭酸 (ACC) 粒子の構造と組成の進化を調査する.
- ACCの高解像度の時間的な研究のための新しい有機溶媒のない方法を開発する.
- ACC粒子の安定性と変換における移動水分の役割を解明する.
主な方法:
- 微流体噴霧乾燥機を使って 空気中のACC粒子を生成した.
- 制御された粒子の形成時間は100msから10sで,高時間解像度の quenching を可能にします.
- 粒子の大きさ,移動性水分量,および安定性との関係を,様々な特徴化技術を用いて分析した.
主要な成果:
- 長時間形成されたより大きなACC粒子は,移動水分を多く含んでいることが示されました.
- 移動性水分量が高くなると,温度による結晶化と電子束分解に対する粒子の安定性が低下することが示された.
- ポリアクリル酸 (PAA) のような有機添加物を含めると,移動水量が減り,運動安定性が向上することが確認された.
結論:
- 形成時間,粒子の大きさ,移動性水分含有量,無形カルシウム炭酸の安定性との関係を確立した.
- ACCの固体変換経路に影響を与える重要な要因として移動水を特定しました.
- ACCの安定性を制御するために添加物を使用する可能性を強調し,特異な性質を持つバイオミメティックなCaCO3材料の製造への道を切り開いた.
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