摘要
目的制备多壁异氰酸酯微胶囊及该微胶囊包埋的聚氨酯(PU)自修复防腐涂层。方法在Pickering乳液中,通过界面聚合、原位聚合、自组装,一步生成由内至外依次为聚脲内膜、酚醛壳、聚甲基丙烯酸缩水甘油酯(PGMA)粒子层的多层囊壁包裹异佛尔酮二异氰酸酯(IPDI)芯材的IPDI微胶囊。通过索式提取实验获得了微胶囊的芯材含量,通过SEM、OM对微胶囊形貌及壳层结构进行观测,通过FTIR、DSC测试研究微胶囊的成分及芯材反应活性,通过EIS、加速腐蚀实验研究微胶囊包埋的PU涂层的自修复防腐性能。结果随着芯壳比的增加,微胶囊的芯材含量增大,当芯壳比为2.5∶1时,芯材含量最大,达70.22%。当芯壳比为1.5∶1时,微胶囊的球形度最好,平均粒径最小,为86.12μm,且分布均一。IPDI微胶囊具有一层聚脲内膜、酚醛壳及PGMA粒子层,IPDI芯材被成功包覆,且保持有效性。IPDI微胶囊的初始分解温度为235.8℃,对芯材起到较好的保护作用。包埋IPDI微胶囊的自修复涂层,划痕修复后的阻抗模量恢复至划痕前初始状态阻抗模量的同量级水平。盐水浸泡192h后,自修复涂层划痕处未见腐蚀产生。结论制备的IPDI微胶囊的芯材含量较高,球形度较好,分布均一。该一步法工艺有助于对活泼性芯材达到高效包覆,多囊壁结构有助于提高微胶囊的热稳定性和有效性。自修复涂层由于划痕处生成了固化膜,从而抑制了腐蚀的产生,具有较好的自修复防腐性能。
The work aims to prepare multi-walled isocyanate microcapsule and the microcapsule-embedded polyurethane(PU) self-healing anticorrosive coating. The wall of IPDI-loaded microcapsule from the inside to the outside were polyurea inner membrane, phenolic outer shell and PGMA particle layer, respectively, which were formed by interfacial polymerization, in-situ polymerization, and self-assembly in the Pickering emulsion. The core contents of the microcapsules were obtained by Soxhlet extraction experiment. The morphology and shell structure of the microcapsules were observed by SEM and OM. The composition and reactivity of the microcapsules were studied by FTIR and DSC tests. The self-healing and anti-corrosion of PU coating embedded the microcapsule were studied by EIS and accelerated corrosion experiments. As the core-shell mass ratio increased, the core content of the microcapsules increased. When the core-shell ratio was 2.5∶1, the core content was the largest and reached 70.22%. When the core-shell ratio was 1.5∶1, the microcapsules had the best sphericity and the smallest mean particle size of 86.12 μm, and were distributed uniformly. IPDI-loaded microcapsules had a layer of polyurea inner membrane, a phenolic shell and a layer of PGMA particles. The IPDI core was successfully encapsuled and remained effective. The initial decomposition temperature of IPDI-loaded microcapsules was 235.8 ℃, which had a good protective effect on the core material. The impedance modulus of self-healing coating embedded IPDI microcapsules after the scratch was restored to the same level compared with that at initial state(before the scratch). After immersed in saline solution for 192 h, no corrosion occurred at the scratch of the self-rehealing coating. IPDI microcapsules have higher core content, better sphericity and uniform distribution. The one-step process can achieve efficient encapsulation on the active core material, and the multi-wall structure is beneficial to improving the thermal stability and effectiveness of th
作者
郑楠
刘杰
李文戈
肖雯
李宗林
ZHENG Nan;LIU Jie;LI Wen-ge;XIAO Wen;LI Zong-lin(Shaanxi Province Key Laboratory of Catalytic Foundation and Application, School of Chemical and Environmental Science, Shaanxi University of Technology, Hanzhong 723001, China;School of Materials Science and Engineering, Shaanxi University of Technology, Hanzhong 723001, China;Merchant Marine College, Shanghai Maritime University, Shanghai 201306, China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2019年第4期262-269,共8页
Surface Technology
基金
陕西省教育厅专项科研计划项目(17JK0134)
陕西理工大学人才启动项目(SLGKYQD2-10)
陕西理工大学大学生创新创业训练计划项目(2018039/20182439)
关键词
异氰酸酯微胶囊
多壁
自修复
防腐
涂层
IPDI-loaded microcapsules
multi-wall
self-healing
anticorrosion
coatings
