合成和描述Poly (urea-formaldehyde) 微囊的合成和表征,其中含有5-乙烯-2-norbornene作为自我愈合剂,并可能用于聚合物复合材料
Sabrina Sara Rossi1, Alexandre Estevão Carrara2, Maria Carolina B Costa3
1Embraer, Rodovia Presidente Dutra, s/n, Km 134, 12247-004 São José dos Campos, SP, Brazil.
Anais da Academia Brasileira de Ciencias
|December 21, 2023
概括
这项研究详细介绍了制造含有自我愈合剂,5-乙烯-2-norbornene的聚尿甲) 微囊的方法. 这些微囊证明了自愈材料的化学兼容性和热稳定性.
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:
- 自愈材料提供增强的耐用性和延长的使用寿命.
- 微封装是将活性剂纳入聚合物的一个关键策略.
- 聚氨酸甲 (PUF) 是微囊的多功能外材料.
研究的目的:
- 开发和表征含有5-乙烯基-2-基 (ENB) 的PUF微囊,用于自我愈合的应用.
- 为了评估ENB和Grubb的催化剂与环氧矩阵的化学兼容性.
- 评估合成的微囊的形态,化学和热性能.
主要方法:
- 粘附测试 (切) 用于兼容性测试.
- 用于微囊合成的油在水乳液系统.
- 扫描电子显微镜 (SEM) 用于形态学和外厚度分析.
- 热重力测量分析 (TGA) 用于热稳定性和释放温度的确定.
主要成果:
- 在环氧矩阵,ENB和Grubb的催化剂之间证明了化学兼容性.
- 合成的PUF微囊与ENB,其颗粒度分散度为30-140μm (平均69.8±4.9μm).
- SEM显示了微囊外的平均厚度为3.6 ± 0.4μm.
- 在230°C以上,TGA表示微囊破裂和ENB释放.
结论:
- 开发的含有ENB的PUF微囊适合创建自愈环氧材料.
- 微囊具有适当的尺寸,外厚度和热稳定性,具有有效的自我愈合功能.
- 通过这种微封装方法,可以成功地将自我愈合能力集成到聚合物矩阵中.
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