应用pH调节以提高含有丁酸作为相变材料的胺-甲微囊的热稳定性
Branko Alič1, Urška Šebenik1, Matjaž Krajnc1
1University of Ljubljana, Faculty of Chemistry and Chemical Technology, Večna pot 113, 1000 Ljubljana, Slovenia.
Polymers
|September 14, 2024
概括
这项研究利用pH调节优化了微封装,以提高热稳定性. 胺-甲基甲 (MF) 微囊与丁酸核心显示了热能存储的性能改善.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 聚合物化学 聚合物化学
背景情况:
- 微封装对于保护核心材料和控制其释放至关重要.
- 胺-甲 (MF) 树脂由于其耐热和耐化学作用,被广泛用于微囊外.
- 提高微囊的热稳定性对于热能存储等应用至关重要.
研究的目的:
- 开发一种使用pH调节的双阶段微封装工艺,以提高MF外微的热稳定性.
- 研究pH值变化对多重凝结率和形态学的影响.
- 为了评估优化微囊的热性能.
主要方法:
- 一个两阶段的微封装过程,涉及pH调节 (6.0-8.0,然后到5.0).
- 在100°C的固化后处理.
- 使用差分扫描热度计 (DSC),电子显微镜 (EM) 和热重力计 (TGA) 的表征.
主要成果:
- 调节pH值为8.0最初减缓了多重凝结,形成了一个更光滑的外.
- 随后的pH值降至5.0,通过进一步的多重凝结,使外变硬.
- 优化的微囊表现出极好的热稳定性,在300°C时体重损失仅为5%,在350°C以上降解.
结论:
- 两阶段的pH调节过程有效地提高了MF微囊的热稳定性.
- 优化的微囊显示出热能储能应用的巨大潜力.
- 这些发现为控制高温应用的MF微囊特性提供了宝贵的见解.
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