作为热潜固剂的部分化聚2-基/基-2-索林:组合和悬挂组对固行为的影响
Saeed Salamatgharamaleki1,2, Asu Ece Atespare1,2, Taha Behroozi Kohlan1,2
1Integrated Manufacturing Technologies Research and Application Center & Composite Technologies Center of Excellence, Sabanci University, Istanbul 34906, Turkey.
ACS omega
|March 3, 2025
概括
聚二/二氧化) -聚乙胺 (POZ-PEI) 共聚合物作为可调节的热隐性固化剂 (TLC) 用于环氧树脂. 具有疏水性侧链和低水解比率的优化TLC具有出色的延迟和稳定性.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
背景情况:
- 聚二/二氧化) -聚乙烯胺 (POZ-PEI) 共聚合物是通过聚二/二氧化 (POZ) 的部分水解合成的.
- 在POZ-PEI中的氨基群为聚合后修饰提供了多功能站点,使可调节性质成为可能.
- 这些共聚合物是环氧树脂系统中热隐性固化剂 (TLC) 的有希望的候选者.
研究的目的:
- 通过不同的悬挂组,摩尔质量和水解比率来合成和描述一系列POZ-PEI共聚物.
- 研究这些结构参数对环氧树脂的热性能和固化行为的影响.
- 为了确定一个组件环氧树脂 (OCER) 的最佳POZ-PEI基TLC,以提高延迟和稳定性.
主要方法:
- 通过对POZ同聚合物的受控水解合成POZ-PEI共聚物.
- 使用1H NMR,FTIR,DSC和TGA进行表征,以分析热和结构性质.
- 通过将POZ-PEI TLC与双甲二甲基乙烯 (DGEBA) 混合,然后进行DSC,风病学和DMA分析来准备和评估OCER.
主要成果:
- 与其前体相比,POZ-PEI共聚物表现出较低的玻璃化过渡温度 (Tg) 和分解温度 (Td).
- 具有疏水侧链,低水解比率和低摩尔质量的TLC显示出优越的延迟.
- 最佳的PPhOZ-PEI-1共聚合物 (Tg = 52 °C) 提供了化学和物理延迟,在40 °C稳定3小时,在60 °C部分固化.
- 风湿学研究表明,PPhOZ-PEI-1-DGEBA OCER的线性粘弹性区域高达10%的剪切应变.
- 固化样本的动态机械分析 (DMA) 显示了在87.6°C的tan δ峰值.
结论:
- POZ-PEI共聚物为环氧树脂固化提供可调的延迟时间,受到侧链疏水性,水解率和摩尔质量的影响.
- 该PPhOZ-PEI-1共聚合物代表了一个有效的TLC,平衡延迟与固化性能.
- 开发的OCER显示出有前途的热力学性能,适合各种应用.
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