化学学报 ›› 2012, Vol. 70 ›› Issue (06): 753-758.DOI: 10.6023/A1108241 上一篇    下一篇

研究论文

高性能自修复微胶囊预聚物组成的研究

顾雪琳, 杨继萍   

  1. 北京航空航天大学材料科学与工程学院空天材料与服役教育部重点实验室 北京 100191
  • 收稿日期:2011-08-24 修回日期:2011-10-31 出版日期:2012-03-28 发布日期:2011-11-22
  • 通讯作者: 杨继萍

Study on the Prepolymer Components of High-Performance Self-Healing Microcapsules

Gu Xuelin, Yang Jiping   

  1. Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beihang University, Beijing 100191
  • Received:2011-08-24 Revised:2011-10-31 Online:2012-03-28 Published:2011-11-22

为了指导高性能自修复微胶囊的制备研究, 利用偏光显微熔点仪、红外光谱和核磁共振氢谱定量研究了微胶囊预聚物组成随反应条件如反应温度、pH 值和甲醛-尿素物质的量比的变化. 研究结果表明, 升高体系温度和pH 值都会显著促进副反应的发生从而降低产物中二羟甲基脲的产率; 而提高甲醛-尿素的物质的量比, 二羟甲基脲的产率增加,同时三羟甲基脲的产率降低. 此外, 还研究了升温过程中反应体系的温度变化情况. 研究发现: 升温速率一定时, 反应体系的温度变化均匀, 没有温度骤变阶段.

关键词: 微胶囊预聚物, 反应温度, 反应pH 值, 甲醛-尿素物质的量比, 核磁共振氢谱

It is well known that the components of microcapsule prepolymers have great influence on the structures and morphologies of the resultant self-healing microcapsules. The synthesis of high-performance self-healing microcapsules is benefited to the presence of high-content multimethylol urea in the reaction system. In this contribution, the components of microcapsule prepolymers prepared under different reaction conditions, including temperatures, pH values and mole ratio of formaldehyde to urea, were studied and quantificationally analyzed using polarized microscopic melting point meter, infrared spectroscopy and 1H NMR spectroscopy. It was found that increasing the temperature and pH value in the reaction system could significantly promote the secondary reaction respectively, resulting in the decreased yield of dimethylol urea in the reaction system. When increasing the mole ratio of formaldehyde to urea, the yield of dimethylol urea in the reaction system increased, and the yield of trimethylol urea decreased simultaneously. Furthermore, the temperature of the reaction system during the heating process was monitored, and it indicated that the temperature changed at a constant path when a fixed heating rate was performed.

Key words: microcapsule prepolymer, reaction temperature, pH value of reaction, molar ratio of formaldehyde to urea, 1H NMR spectroscopy