在纳米孔丰富的水泥糊中减少收缩,基于蒙莫里隆石的简单有机修饰
Fengyuan Yang1, Ying Yang1, Shaoyou Chen2
1State Key Laboratory of Environmentally Friendly Energy Materials, School of Materials and Chemistry, Southwest University of Science and Technology, Mianyang 621010, China.
Materials (Basel, Switzerland)
|February 24, 2024
概括
使用 cetyltrimethyl ammonium bromide (CTAB) 的蒙莫里隆石的有机修饰有效地减少了水泥糊的收缩. 这种新的方法提高了纳米孔丰富的水泥的性能,对密度和导热率的影响最小.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 土木工程 土木工程是指土木工程.
背景情况:
- 蒙莫里隆石是一种粘土矿物,在水泥材料中具有潜在的应用.
- 控制水泥中的收缩对于耐用性和性能至关重要.
- 有机修饰可以改变粘土的特性,用于特定的应用.
研究的目的:
- 用 cetyltrimethyl ammonium bromide (CTAB) 来实现蒙莫里隆石的有机修饰.
- 用于制造蒙莫里隆尼特诱导的纳米孔丰富水泥糊 (MNCP).
- 调查MNCP的收缩行为和基本性能.
主要方法:
- 通过80°C与CTAB的离子交换对蒙莫里隆石进行有机改性.
- 使用改性蒙莫里隆石作为孔形成剂制造MNCP.
- 自生和干燥收缩,干燥密度,导热率和强度的评估.
主要成果:
- 蒙特莫里隆石的成功有机改性通过阴离子交换得到证实.
- 显著减少了28天的自身缩 (例如,在400公斤/米3时2.05毫米/米).
- 显著减少了28天的干燥收缩率 (高达68.1%).
- 扩大的膜间孔和疏水效应有助于减少收缩.
- 对干燥密度和导热率的影响很小,具有潜在的强度增强.
结论:
- 蒙特莫里隆石的有机改造是可行的和有效的.
- 与传统的水泥糊相比,MNCP的收缩率显著降低.
- 改性蒙莫里隆石作为一种有效的孔形成剂,改善了水泥糊的性能.
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