在玻璃碳的结构进化研究基于年轻的模块的温度依赖性
Yi Yang1, Yanpei Dang1, Haihui Ruan1
1Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong.
Materials (Basel, Switzerland)
|July 14, 2023
概括
这项研究揭示了在热解过程中形成玻璃碳 (GC) 和结构变化的关键500-600°C温度范围. 了解这个范围是从散装前体中进行经济高效的大规模GC生产的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 聚合物化学 聚合物化学
背景情况:
- 玻璃碳 (GC) 是一种硬,惰性材料,通常通过昂贵的粉末前体压缩制成.
- 大量前体的直接热解提供了更便宜的途径,但需要了解碳结构的形成.
- 目前用于工业规模GC生产的方法由于前体加工而昂贵.
研究的目的:
- 为了研究在热解过程中GC的模数的温度依赖的变化.
- 确定影响GC形成和结构演变的临界温度范围.
- 探索从散装树脂中低成本直接合成GC的潜力.
主要方法:
- 在1000°C的烯酸树脂的热解.
- 冲动激发技术 (IET) 用于测量温度依赖的模量.
- 在重新加热GC样本时分析结构改造和刚度变化.
主要成果:
- 确定了500-600°C的临界温度范围,在那里发生了显著的密度变化,导致GC形成.
- 在这个500-600°C范围内的GC样本的再加热诱导了结构改造和降低了刚度,特别是在加热速度>3°C/分钟时.
- 在500-550°C之间火GC导致恢复效果,增加了硬度.
结论:
- 关键的500-600°C温度范围对于玻璃碳的初始形成和随后的结构改造至关重要.
- 了解这些取决于温度的现象对于开发高效,直接和大规模的GC生产方法使用散装前体至关重要.
- 这些发现对优化GC合成工艺具有重大意义,可能降低制造成本,并使更广泛的工业应用成为可能.
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