悬挂组 循环烯的功能化用于高温和高密度储能
Stuti Shukla1, Chao Wu2, Ankit Mishra3
1Department of Chemistry, University of Connecticut, Storrs, CT, 06269, USA.
Advanced materials (Deerfield Beach, Fla.)
|May 20, 2024
概括
新型基替代聚氧甲基化物 (PONB) 提供可调节的高温稳定性,用于先进的能量存储. 这些灵活的聚合物介电材料实现了高能量密度和分解强度,这对于电气化至关重要.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 介电材料 介电材料
背景情况:
- 高温柔性聚合物介电材料对于高密度的能量储存和转换至关重要.
- 设计具有高带隙,介电常数和玻璃过渡温度的聚合物是一个重大挑战.
研究的目的:
- 开发具有可调节的热稳定性和不妥协的大带隙的新型高温烯聚合物.
- 调查素替代剂对聚氧甲胺 (PONB) 的热电性和介电性质的影响.
主要方法:
- 通过在双循环主链聚合物的芳香悬挂组上使用不同的素替代剂合成了一类高温烯酸.
- 利用分子动力学模拟和超快的红外光谱学来分析自由体积和链条放松.
- 其特点是热稳定性,玻璃过渡温度和分解强度.
主要成果:
- 在PONB悬挂组上的素替代调整了玻璃过渡温度从220到245°C.
- 实现了高分解强度 (625-800 MV/m) 和记录的能量密度7.1J/cc在200°C与p-POClNB.
- 观察到可调节的自由体积和基于素类型和位置的链松 (相对于正体) 由于硬质效应.
结论:
- 设计PONB的吊组有效地提高了高密度电气化应用的热稳定性.
- 介电常数和带隙保持稳定,而热特性是可调的.
- 这项研究为苛刻的能源应用提供了高性能聚合物介电材料的途径.
相关概念视频
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