三聚氰胺-甲醛树脂包裹环氧树脂微胶囊的制备及表征  

PREPARATION AND CHARACTERIZATION OF POLY(MELAMINE-FORMALDEHYDE) WALLED MICROCAPSULES CONTAINING EPOXY

作　　者：袁彦超[1] 容敏智[1] 章明秋[1] 

机构地区：[1]聚合物复合材料及功能材料教育部重点实验室中山大学材料科学研究所,广州510275

出　　处：《高分子学报》2008年第5期472-480,共9页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号50573093;U0634001)资助项目

摘　　要：针对环氧树脂基材料的自修复,选取四氢邻苯二甲酸二缩水甘油酯作为芯材,采用三聚氰胺-甲醛树脂为壁材,对其进行微胶囊化包裹.结果表明,制得的具有单囊结构的环氧树脂微胶囊,胶囊粒径较小(约6.7μm)、囊壁较薄(约0.2μm)、芯含量较高(83.2 wt%),囊壁内、外表面光滑致密,胶囊具有良好的密闭性和耐热性;在微胶囊化过程中,三聚氰胺-甲醛树脂的缩聚反应动力学起关键作用,芯材没有参与囊壁形成的交联反应;包裹后的芯材活性保持不变,胶囊被复合到材料过程中囊芯活性也保持不变;胶囊的强度较高,能承受与基体材料复合过程中的外力作用,且与基体材料间粘结良好,在裂纹形成过程中能够随基体同时开裂.Microcracks are easily generated inside polymers and polymer composites during their service in structural applications. Development and coalescence of microcracks would bring about catastrophic failure of the materials and then reduce their lifetimes. Therefore, early sensing, diagnosis and repair of microcracks become necessary for removing the latent perils. In this context, the materials possessing self-healing function are ideal for long-term operation. Attempts have been made to develop solutions in this filed, among which the route based on microcapsulation seems to be promising. Self-repairing polymer composites containing microencapsulated healing agent have attracted more and more research interests. The present article analyzed the existing problems and proposed the criteria for manufacturing qualified microencapsulated healing agent. Accordingly, microcapsules containing epoxy resin were successfully fabricated by in situ polymerization in an oil-in-water emulsion with poly（melamine-formaldehyde） （PMF） as the shell material and high-activity low-viscosity diglycidyl tetrahydro-o-phthalate （DTP） as the core substance. The typical synthesis procedures are described below. About 50 g DTP wasadded into 250 mL aqueous solution of 2% styrene-maleic sodium （SMS） .The mixture was vigorously agitated by a homogenizer for 10 min at a selected rate and then two drops of 1-octanol were added to eliminate surface bubbles of the emulsion. The pre-condensate of 12.5 g melamine and 27.1 g formaldehyde was prepared at 70 - 75 ~C for 30 min, and the pH value of the solution was kept at about 9 - 10 by adding triethanolamine. Subsequently, the precondensate solution was added to the above emulsion with 450 r/min continuous mechanical stirring by a two-bladed stirring paddle while the pH value of the solution was adjusted by adding citric acid. Eventually, the reaction mixture was cooled down to room temperature. The resultant slurry was neutralized by 2 % sodium carbonate solution, and then diluted with

关 键 词：自修复 环氧树脂 三聚氰胺-甲醛 微胶囊 

分 类 号：TQ320[化学工程—合成树脂塑料工业]