由纤维素纳米纤维稳定的皮克林乳液具有可调的表面特性,用于储存热能
Yingying He1, Chunyu Wang1, Yijun Liu2
1State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
International journal of biological macromolecules
|September 26, 2024
概括
纤维素纳米纤维 (CNFs) 有效地稳定了六个多月的乳液. 具有高电荷密度的优化CNF提高了稳定性,并使热能存储应用成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 合体和表面化学
- 可再生材料可再生材料
背景情况:
- 纤维素纳米纤维 (CNF) 以其两性和乳化特性而闻名,使其成为适合的可再生乳化剂.
- 了解碳酸盐群含量和表面电荷密度对CNF乳化能力和皮克林乳液稳定性的影响至关重要.
- 开发稳定的皮克林乳液对于热能存储等应用至关重要.
研究的目的:
- 调查碳酸盐组含量和表面电荷密度对碳酸甲基化CNF的乳化性能的影响.
- 优化CNF以提高皮克林乳液稳定性,并探索它们在热能存储方面的潜力.
- 阐明在乳液中CNF的界面稳定机制.
主要方法:
- 纤维素纳米纤维 (CNF) 的碳氧甲基化,通过使用乙酸的以太化.
- 高压均质化以控制CNF大小和表面电荷密度.
- 用优化的CNF稳定水乳液中制备和表征 (PW)
- 评估乳液稳定性,界面吸附和热性能.
主要成果:
- 优化的CNF表现出高的Zeta潜力 (-71.2 mV) 和碳酸盐含量 (1.81 mmol/g).
- CNFs不可逆地吸附在PW滴水表面上,形成硬体屏障和静电排斥,防止凝聚.
- 经CNF稳定的PW乳液表现出长期存储稳定性 (> 6个月).
- 冷干燥乳液显示高相变 (193.7 J/g),表明可逆热储能.
结论:
- 具有优化的表面性能的碳氧甲基化CNF为皮克林乳液提供了强大的稳定性.
- 该研究提供了 CNF 界面吸附和静电排斥机制的见解,以实现乳液稳定性.
- 优化的CNF显示出在热能储能系统中应用的巨大潜力.
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