环氧网中的液晶性:热导和结构的系统研究
Elias Chalwatzis1, Peng Lan2, Frank Schönberger1
1Fraunhofer LBF, 64289 Darmstadt, Germany.
Polymers
|October 16, 2025
概括
这项研究研究了环氧树脂的导热率 (TC),发现值在0.13-0.32W/m·K之间. 之前报告的高TC和环氧配方中的结晶性在测试条件下没有复制.
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
背景情况:
- 环氧树脂在苛刻的行业中至关重要,但受到低导热率 (TC) 的限制.
- 最近的研究表明,液晶或晶体环氧配方可以达到更高的TC (>1W/(m·K)).
研究的目的:
- 调查特定环氧配方实现增强导热性的潜力.
- 为了将热导率与晶体或液晶域的存在相关联.
主要方法:
- 合成了17种环氧配方,包括基于DGEBA,TME4和LCE-DP的系统.
- 使用激光闪光分析 (LFA),修改过渡平面源 (MTPS),时间域热反射率 (TDTR) 和位移热光学相谱学 (D-TOPS) 测量导热率.
- 使用小角度和广角X射线散射 (SAXS/WAXS) 分析了结晶性/液晶性.
主要成果:
- 所有测试的环氧配方均显示TC值在0.13至0.32W/m·K之间.
- 以前报道的TME4-DDS系统接近1W/m·K,测量在0.26-0.30W/m·K之间.
- 没有观察到强烈的结晶性证据;局部排序并没有显著增加TC.
结论:
- 针对特定环氧配方的先前研究报告的高导热率没有被复制.
- 在测量方法之间观察到的TC变化是显著的,有时超过从中位相形成的收益.
- 在交叉连接的环氧热中显著结晶性的证据仍然很弱,这表明交叉连接阻碍了长距离的订购.
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