低粘度和低温度固化反应性POSS/环氧混合树脂,具有增强的性和全面的热性能
Ruiyan Han1, Xiaoyan Ma1, Lifeng Cai1
1School of Chemistry and Chemical Engineering, Northwestern Polytechnical University Xi'an 710072 PR China m_xiao_yana@nwpu.edu.cn.
RSC advances
|March 4, 2024
概括
这项研究开发了一种新型的环氧混合树脂系统 (OPEP),使用八环氧终结多面体寡合物丝氧 (OG-POSS) 进行增强的低温固化. 欧佩克系统显著改善了机械性能和热稳定性,克服了传统硬化方法的局限性.
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
- 纳米技术纳米技术
背景情况:
- 在低温固化过的环氧树脂具有较差的机械和耐热性能.
- 环氧树脂的传统硬化方法通常会损害其热稳定性,限制实际应用.
- 需要高性能环氧树脂,可以在低温下固化而不会牺牲关键性质.
研究的目的:
- 开发一种低粘度,低温固化环氧混合树脂系统 (OPEP),具有增强的机械和热性能.
- 为了研究反应性八环氧终结多面寡合物丝素 (OG-POSS) 作为硬化修饰剂的作用.
- 为制备适用于低温固化应用的高性能环氧树脂提供指导.
主要方法:
- 使用E-51环氧树脂,MHHPA固化剂,DMBA加速器和OG-POSS修饰器制备一个环氧混合树脂系统 (OPEP).
- 评估可加工性,包括粘度和加工窗口.
- 机械性能 (冲击强度,屈曲强度,拉伸强度,破裂时延长) 和热性能 (分解温度,玻璃过渡温度,热扭曲温度) 的表征.
- 使用Šesták-Berggren自催化模型分析固化动力学.
主要成果:
- 欧佩克系统表现出优异的加工能力,粘度低,加工窗口长,适合低温固化.
- OG-POSS显示出卓越的兼容性和反应性,促进了环氧树脂固化,并略微降低了激活能量 (Eα).
- 机械性能有显著的改善:冲击强度增加了55.97%,屈曲强度增加了3.1%,拉伸强度增加了64.68%,断裂时的延长增加了26.51%.
- 热性能得到了增强:热分解温度 (Td5) 增加了13.0°C,玻璃过渡温度 (Tg) 增加了2.3°C,热扭曲温度 (THDT) 增加了6.8°C,这归因于OG-POSS.的无机结构.
结论:
- 开发的OPEP系统有效地提高了低温固化的环氧树脂的性和热稳定性.
- 整合OG-POSS提供了一种可行的策略,可以在不损害热阻力的情况下创建高性能环氧树脂.
- 这项研究为使用有机-无机纳米混合材料在环氧树脂中协调优化性和热稳定提供了宝贵的见解.
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