基于自修复涂料的脲醛树脂微胶囊的制备及其表征

Preparation and Characterization of Urea-Formaldehyde Resin Microcapsules for Self-Healing Coatings

目前,关于包覆桐油的脲醛树脂微胶囊用于自修复涂料的制备研究较少。以桐油为芯材,采用原位聚合方式在桐油表面制备了脲醛树脂微胶囊;采用扫描电镜(SEM)、光学显微镜(OM)、热重分析仪(TGA)以及红外光谱(IR)对胶囊的微观形貌、热稳定性及化学结构进行了表征。结果表明:当预聚合反应p H=8.5,采用OP-10作为乳化剂,其用量为芯材质量的5%,搅拌转速为900 r/min,并控制酸化时间为90 min时,可制得外形完整、尺寸均匀的球形微胶囊,微胶囊表面略粗糙,其直径约为200μm,包封闭率达85.1%,其初始热分解温度为205℃左右。

Urea-formaldehyde resin microcapsules for self-healing coating were prepared by in-situ polymerization with tung oil as core material.The surface micro-morphology of the microcapsules was observed by optical microscope and SEM.The chemical structure and thermal stability of the microcapsules were analyzed by FT-IR and thermal gravimetric analyzer respectively.Results showed that the initial decomposition temperature of the capsule wall was about 205 ℃.The optimal conditions were obtained as follows：pH =8.5 for pre-polymerization,emulsifier （OP-10） dosage of 5%,stirring rate of 900 r/min,and acidification time of 90 min.The prepared microcapsules were characterized by spherical shape with a rough surface and an average diameter of 200 μm,and the envelop rate reached 85.1%.