炭素改変セメントの低フィールドNMR:分散と水分化の研究
Mihai M Rusu1,2, Karoly Mostis1,2, Codrut Costinas3,4
1Department of Physics and Chemistry, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, Romania.
Materials (Basel, Switzerland)
|February 13, 2026
まとめ
この研究では,NMRリラクソメトリーを使用して,炭黒 (CB) と超可塑剤 (SP) がセメントの水分化と微細構造にどのように影響するか理解しています. SPは水分化を遅らせ,毛孔網を精製し,セメント材料におけるCB分散を助長することを明らかにした.
科学分野:
- マテリアルサイエンス 材料科学
- 物理化学 物理化学
- 土木工学 土木工学とは
背景:
- セメントの水分化を理解することは,先進的なセメント材料の開発に不可欠です.
- 炭素ベースの充填剤と超可塑剤は,セメントの特性に影響を与える重要な成分です.
- フィルラーの分散と水分をリアルタイムで評価するには,破壊的でない技術が必要です.
研究 の 目的:
- 炭黒 (CB) とアクリル超可塑剤 (SP) がセメントの水分化と微細構造に及ぼす影響を調査する.
- 固体材料におけるCBの分散に関するNMRベースの洞察を提供するため.
- 総合的な分析のために,NMRの発見を他の特徴づけ方法と相関させる.
主な方法:
- ローフィールドNMRリラクソメトリー (in situおよびex situ) を用いて,セメントの水分化とCB分散をモニタリングした.
- ダイナミック・ライト・スキャタリング (DLS) と ζ-ポテンシャル測定により,CB/SP混合物のコロイド安定性を評価した.
- 光学顕微鏡 (OM) と超音波パルス速度 (UPV) を用いて,加熱したサンプルを補完的に分析した.
主要な成果:
- NMRは,炭素インク信号とセメントペースト信号をうまく区別し,CB分散の非破壊的な評価を可能にしました.
- スーパープラスチック剤 (SP) の添加は,セメントの水分化を遅らせ,毛穴ネットワークを精製することが示されました.
- CBの粒子分散の改善は,SP用量を増加させると観察され,NMRとUPVによって確認されました.
結論:
- NMRリラクソメトリーは,新鮮なセメントペーストの炭素ベースの充填剤分散を非破壊的に評価するための強力なツールです.
- スーパープラスチック化剤は,セメントの水分化運動を制御し,添加物の分散を改善する上で重要な役割を果たします.
- NMR,DLS,z-ポテンシャル,OM,UPVの組み合わせは,セメント材料を特徴付けるための堅固なアプローチを提供します.
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