使用疏水性吸烟填充剂增强聚胺薄膜的机械和热性能
Jongin Yeob1,2, Sung Woo Hong2, Won-Gun Koh1
1Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Polymers
|January 26, 2024
概括
改性烟 (FS) 颗粒增强了聚胺 (PI) 复合膜. 甲基化FS颗粒,特别是PI/3-FS,在保持光学和热稳定性时显著改善了拉伸模量和性等机械性能.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 聚胺 (PI) 薄膜在先进的应用中至关重要,但通常需要增强的机械性能.
- 烟 (FS) 颗粒为复合材料改进提供了一条路径,但表面修改是兼容性的关键.
- 优化填充剂-矩阵相互作用对于实现PI复合材料所需的性能至关重要.
研究的目的:
- 调查各种修饰的烟 (FS) 颗粒对聚胺 (PI) 复合膜的机械,光学和热性能的影响.
- 为了确定最佳的FS修改来提高PI复合材料的性能.
- 在复合材料制造过程中保持PI矩阵固有的光学和热特性.
主要方法:
- 使用化二胺,化二化和双二化通过化学模拟合成PI矩阵.
- 将未修改的 (0-FS) 和修改的FS粒子 (二甲基,三甲基,八甲基,D4,PDMS) 纳入PI矩阵.
- 使用扫描电子显微镜 (SEM),吸附-溶解,水接触角测量,拉伸测试和热分析 (DSC,TGA) 的表征.
主要成果:
- 甲基化FS颗粒 (2-FS和3-FS) 显著改善了PI复合材料的机械性能,PI/3-FS显示拉伸模量增加了10%以上,性提高了15%.
- 更长链的FS粒子 (8-FS,D4-FS) 增加了拉伸模量,但降低了性.
- 修改PDMS-FS导致兼容性差,聚合,以及机械和光学性能降低.
- 大多数复合膜保持了高光学传导率 (>86%在550nm),并且在很大程度上保持了热稳定性.
- PI/3-FS薄膜表现出增强的尺寸稳定性与降低的热膨胀系数 (34.5 ppm/°C).
结论:
- 雾化的表面修饰对于有效增强聚胺复合材料至关重要.
- 甲基化烟,特别是三甲基修饰的FS (3-FS),为提高PI薄膜的机械性能 (模量,性) 和尺寸稳定性提供了有希望的方法.
- 需要仔细选择FS修改,以避免对光学性能和机械性能产生不利影响,如PDMS-FS所见.
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