导热的纳夫他林环氧树脂通过定制灵活的链条长度和液晶结构
Shuangshuang Wang1, Kunpeng Ruan1, Yongqiang Guo1
1Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, P.R. China.
Angewandte Chemie (International ed. in English)
|March 11, 2025
概括
研究人员开发了基于的新型液晶环氧树脂 (LCEs),以提高导热性. 优化的LCE具有改进的热管理特性,为电子应用提供了一个有前途的替代方案.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 具有高导热率 (λ) 的环氧树脂对于电子包装,粘合和涂层至关重要.
- 目前的高λ环氧树脂通常具有高的液晶过渡温度和由于它们的 mesogenic 单元的可加工性差.
研究的目的:
- 合成和描述基于的新型液晶环氧单体 (LCE) 和它们的固化树脂 (LCER).
- 为了研究灵活链条长度对以纳烯为基础的LCERs特性的影响.
- 开发具有低液晶过渡温度,高热导率和优良的热管理机械性能的环氧树脂.
主要方法:
- 合成基于纳夫他林的液晶环氧单体,具有不同的灵活链条长度.
- 在液晶阶段内固化LCE,以形成纳夫他林液晶环氧树脂 (LCER).
- 网络顺序的表征,旋转半径,低频振动密度的状态,液晶过渡温度,导热率 (λ),耐热指数和存储模块.
主要成果:
- 网络顺序,旋转半径和低频振动密度的状态显示出初始增加,随后随着灵活链条长度的增加而下降.
- LCER2 (三碳弹性链) 显示了这些参数的最大值,增强了声子扩散和导热性.
- LCER2实现了0.40 W m-1 K-1的λ,液晶过渡温度为67-78°C,耐热指数为158.8°C,存储模量为2059 MPa,显著优于E-51树脂.
结论:
- 灵活的链条长度是优化烯基LCER特性的一个关键因素.
- 开发的LCER2在导热性 (比E-51树脂高2.2倍) 和机械性能方面取得了显著的改进.
- 这项研究为设计用于先进热管理应用的高性能环氧树脂提供了一条途径.
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