新型碳纳米管改性密胺树脂相变微胶囊的制备及性能表征

发布时间：2018-04-28 19:23

本文选题：相变微胶囊 + 碳纳米管　；参考：《深圳大学》2017年硕士论文

【摘要】：能源紧缺和环境恶化已经成为全球性的焦点问题,节约能源,改变能源利用方式,开发新的能源类型成为解决这一问题的重要举措。相变材料是一类可通过自身相态转变而进行热能存储和释放的材料,因而在能量存储和温度调控领域有着广阔的应用前景。本课题主要研究相变储能微胶囊的应用与改性,针对传统相变微胶囊的导热性能差,机械性能不足且存在过冷现象等问题,尝试引入一种导热性能好,机械性能优异的无机粒子填料,制备出有机-无机复合的相变微胶囊,再通过不同的科学研究手段来对相变微胶囊进行表征分析。例如:通过光学显微镜(OM),扫描电镜(SEM),透射电镜(TEM),原子力显微镜(AFM)及Zetasizer对微胶囊的形貌,粗糙度以及表面电性进行表征和分析,通过差示扫描量热仪(DSC)和热重分析仪(TGA)对微胶囊的储热性能和热稳定性进行表征和分析,通过红外光谱仪(FTIR)和X射线衍射仪(XRD)对微胶囊的组成和结构进行表征和分析,通过红外热成像仪(FLIR)和Hot Disk热常数分析仪(TCA)对微胶囊的调温性能和导热性能进行表征和分析,通过纳米压痕仪(Nanoindenter)对微胶囊的力学性能进行表征和分析。主要得出以下结论:(1)我们通过静电吸引和氢键作用,在密胺树脂相变微胶囊的表面进行层层自组装改性,成功制备了具有双壳层结构的相变微胶囊。结果表明,碳纳米管的组装能够很好地促进相变微胶囊的熔融和结晶过程,有效地抑制过冷度,使潜热能够更快地进行储存和释放。而且碳纳米管的组装很好地改善了相变微胶囊的力学性能和导热性能,当组装4个(聚苯乙烯磺酸钠/氨基化碳纳米管)((PSS/A-CNTs))双层时,其平均硬度,杨氏模量和导热性能相比纯密胺树脂相变微胶囊,分别提高了230%,32.1%,57.89%。(2)当壁材掺杂羧基化碳纳米管(C-CNTs)后,其表面变得相对粗糙,附着有大量蠕虫状的碳纳米管,但相变微胶囊的热稳定性有明显的提高,另外碳纳米管的掺杂不仅能够有效地提高密胺树脂相变微胶囊的导热性能,而且能够显著改善相变微胶囊的抗压能力和强度,其最大负载压力,平均硬度以及杨氏模量相比纯的密胺树脂微胶囊分别提高了55.1%,60.0%以及30.9%。(3)当芯材掺杂烷基化碳纳米管(i-CNTs)后,基本不影响相变微胶囊的表面形貌和力学性能,但在破裂的芯材中能清晰地看到蠕虫状的CNTs,而且芯材掺杂i-CNTs后能够显著地抑制相变微胶囊的过冷度。(4)通过相变微胶囊/环氧树脂复合材料的导热系数测试我们可以发现,碳纳米管的层层自组装改性和物理掺杂改性均能有效地改善密胺树脂相变微胶囊的导热性能。由红外热成像的表征可以得出,相变微胶囊具有很好的调温性能,能够对复合材料的升温和降温过程起到一定的缓冲作用,有效减少温度波动。
[Abstract]:Energy shortage and environmental deterioration have become the focus of the global problem. Saving energy, changing the way of energy utilization and developing new energy types are the important measures to solve this problem. Phase change material (PCM) is a kind of material which can store and release heat energy through its phase transition, so it has a wide application prospect in the field of energy storage and temperature control. This paper mainly studies the application and modification of phase change energy storage microcapsules. Aiming at the problems of poor thermal conductivity, insufficient mechanical properties and undercooling phenomena of traditional phase change microcapsules, we try to introduce a kind of good thermal conductivity. The organic-inorganic composite phase change microcapsules were prepared with excellent mechanical properties of inorganic particles. The phase change microcapsules were characterized by different scientific research methods. For example, the morphology, roughness and surface electrical properties of microcapsules were characterized and analyzed by optical microscope, scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscope (AFM) and Zetasizer. The thermal storage and thermal stability of microcapsules were characterized and analyzed by differential scanning calorimeter (DSC-DSC) and thermogravimetric analyzer (TGA). The composition and structure of microcapsules were characterized and analyzed by FTIR and XRD. The thermoregulation and thermal conductivity of microcapsules were characterized and analyzed by infrared thermal imager (FLIR) and Hot Disk thermal constant analyzer. The mechanical properties of microcapsules were characterized and analyzed by nano-indentation instrument. The main conclusions are as follows: (1) by electrostatic attraction and hydrogen bonding, we successfully prepared phase change microcapsules with double shell structure by layer self-assembly modification on the surface of phase change microcapsules of melamine resin. The results show that the assembly of carbon nanotubes can promote the melting and crystallization of phase change microcapsules effectively restrain the undercooling and make the latent heat be stored and released more quickly. Moreover, the assembly of carbon nanotubes improves the mechanical properties and thermal conductivity of phase change microcapsules, and the average hardness of four (sodium polystyrene sulfonate / carbon amino-carbon nanotubes) bilayers is obtained. Compared with the phase change microcapsules of pure melamine resin, the Young's modulus and thermal conductivity were increased by 230% ~ 32. 1 and 57.89. 2) when the wall materials were doped with carboxylated carbon nanotubes (C-CNTs), the surface became relatively rough and a large number of wormlike carbon nanotubes were attached to them. However, the thermal stability of phase change microcapsules was improved obviously. In addition, the doping of carbon nanotubes could not only effectively improve the thermal conductivity of phase change microcapsules of melamine resin, but also improve the compressive resistance and strength of phase change microcapsules. The maximum loading pressure, average hardness and Young's modulus were increased by 55.1% and 30.9%, respectively, compared with the pure melamine resin microcapsules. When the core material was doped with alkylated carbon nanotubes (i-CNTs), the surface morphology and mechanical properties of the phase change microcapsules were not affected. However, the wormlike CNTs can be seen clearly in the cracked core, and the supercooling degree of phase change microcapsules can be significantly inhibited by doping i-CNTs into the core material.) the thermal conductivity of phase change microcapsules / epoxy resin composites can be measured by the thermal conductivity test. Layer by layer self-assembly modification and physical doping modification of carbon nanotubes can effectively improve the thermal conductivity of phase change microcapsules of melamine resin. From the characterization of infrared thermal imaging, it can be concluded that the phase change microcapsules have good temperature-regulating properties, which can play a certain role in cushioning the temperature and cooling process of the composites, and effectively reduce the temperature fluctuation.
【学位授予单位】：深圳大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB34

【相似文献】