酸盐桥接单体对法索二热的热氧化行为的影响
Marina Sergeevna Lobanova1, Alexandr Vladimirovich Babkin1, Alexey Valeryevich Kepman1
1Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
Polymers
|August 29, 2024
概括
在热中优化酸盐桥接双甲单体 (PPhPN) 提高了可加工性和高温稳定性. 10-15%的PPhPN含量确保了高达300°C的优异的热氧化稳定性.
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
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚乙烯热为苛刻的应用提供卓越的机械,化学和阻燃性能.
- 之前的工作确立了酸盐桥接双甲单体可以提高树脂的可加工性.
- 评估长期高温稳定性对于实际的热应用至关重要.
研究的目的:
- 研究 bis(3-(3,4-dicyanophenoxy) phenyl) phenyl phosphate (PPhPN) 单体度对耐热性质的影响.
- 确定最佳的PPhPN含量,以平衡可加工性和长期热稳定性.
- 评估材料在热氧化老化条件下的性能.
主要方法:
- 合成和表征了具有不同PPhPN单体含量的phthalonitrile树脂.
- 进行了机械测试 (屈曲强度,弹性模量) 和物理化学分析.
- 进行了热重力测量分析 (TGA) 和长期热氧化衰老研究.
主要成果:
- 树脂可加工性受到15%PPhPN以下的晶相形成的阻碍.
- 高PPhPN含量降低了热氧化稳定性.
- 最佳的PPhPN度 (10-15%) 产生易于加工和优良的稳定性高达300°C.
结论:
- 10-15%的PPhPN含量优化了phthalonitrile热的可加工性和长期的热氧化稳定性.
- 经过优化的树脂在老化后保持高曲强度 (>120 MPa) 和模量 (4.3 GPa).
- 长期衰老研究对于全面的热稳定性评估至关重要.
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