Icduygu M Galip, Asilturk Meltem, Yalcinkaya M Akif, Hamidi Youssef K, Altan M Cengiz
School of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73072, USA.
School of Civil Aviation, Giresun University, Giresun 28200, Turkey.
Materials (Basel). 2019 Apr 29;12(9):1387. doi: 10.3390/ma12091387.
The three-dimensional nano-morphology of poly(methyl methacrylate; PMMA) microcapsules filled with carbon nanotubes (CNTs) and epoxy resin were investigated by various microscopy methods, including a novel, laser scanning confocal microscopy (LSCM) method. Initially, PMMA microcapsules containing various amounts of CNTs were synthesized by a solvent evaporation method. Scanning electron microscopy analysis showed that pore-free, smooth-surface microcapsules formed with various types of core-shell morphologies. The average size of CNT/epoxy/PMMA microcapsules was shown to decrease from ~52 μm to ~15 μm when mixing speed during synthesis increased from 300 rpm to 1000 rpm. In general, the presence of CNTs resulted in slightly larger microcapsules and higher variations in size. Moreover, three-dimensional scans obtained from confocal microscopy revealed that higher CNT content increased the occurrence and size of CNT aggregates inside the microcapsules. Entrapped submicron air bubbles were also observed inside most microcapsules, particularly within those with higher CNT content.
采用包括一种新型激光扫描共聚焦显微镜(LSCM)方法在内的各种显微镜方法,研究了填充有碳纳米管(CNT)和环氧树脂的聚甲基丙烯酸甲酯(PMMA)微胶囊的三维纳米形态。最初,通过溶剂蒸发法合成了含有不同量碳纳米管的PMMA微胶囊。扫描电子显微镜分析表明,形成了具有各种核壳形态的无孔、表面光滑的微胶囊。当合成过程中的混合速度从300转/分钟增加到1000转/分钟时,CNT/环氧树脂/PMMA微胶囊的平均尺寸从约52μm减小到约15μm。一般来说,碳纳米管的存在导致微胶囊略大且尺寸变化更大。此外,共聚焦显微镜获得的三维扫描结果显示,较高的碳纳米管含量增加了微胶囊内碳纳米管聚集体的出现和尺寸。在大多数微胶囊内部也观察到截留的亚微米气泡,特别是在碳纳米管含量较高的微胶囊中。