微胶囊复合相变储能材料的制备与表征.docVIP

摘 要 近年来，随着能源问题的加剧，相变蓄能材料受到越来越多的关注。相变储能材料因其在相变的过程中能够吸收或释放大量的热，可以起到控温和储能的作用，能够解决能量供求在时间和空间上分配不平衡的矛盾，是提高能源利用率的有效手段。它可以广泛应用于航空航天、太阳能利用、工业余热回收、采暖空调及家用电器等领域。石蜡是应用非常广泛的一类相变材料，具有许多优点，但存在着固液相变体积变化大、泄露以及传热差等缺点。将石蜡微胶囊化能很好的解决上述问题，因此成为近年来研究的热点。 本论文以三聚氰胺-甲醛为壁材，石蜡为芯材，采用原位聚合法制备相变材料微胶囊。并采用扫描电子显微镜(SEM)、差示扫描量热仪(DSC)、红外光谱（FTIR）等测试仪器对相变材料微胶囊的表面形貌、粒径大小、分子结构、热性能进行了表征和分析。实验结果表明，用微胶囊包裹石蜡明显的降低了石蜡的相变焓；以SDBS和OP为乳化剂制备的微胶囊表现出了比较好的性能；加入间苯二酚比较好的增加了壁材的柔性。 关键词：相变材料；微胶囊；原位聚合；三聚氰胺一甲醛；石蜡 Abstract In recent years，With the acceleration of the energy crisis, Phase change materials (PCM) has been more and more concerned. PCM can absorb，store，and release large amounts of latent heat over a defined temperature range while undergoing phase changes.thus,they have gained a great scientific interest in modern technology due to the impending shortage and increasing cost of energy Resources. Paraffin is a kind of phase change materials and has a lot of merits being widely used in industry．But it has the disadvantage of volume changed greatly when changing phase，low effidency of heat transfer as well as leakage．Microencapsulated paraffin can be such a good solution to these problems,so the research is focused in recent years. Phase-Change Materials Microencapsule (microPCMcs) was prepared by in- situpolymerization using melamine- formaldehyde resin as the shell and paraffin as the core．The characterization of the microcapsules，including the morphology,particle size，Molecular Structure ，thermal properties and stability,was systematically analysed by SEM，DSC，FTIR. Experimental results show that microencapsulated paraffin reduced the enthalpy significantly; With SDBS and OP as the emulsifier showed good performance;By adding resorcinol the shell increases the Flexibility. Keywords：Phase-Change Materials； Microencapsule； in-situpolymerization；melamine-formaldehyde resin；paraffin PCM 相变储能材料 △G 相变储能材料在相变前后自由能变化的差值，kJmol-1 △S 相变储能材料在相变过程中的熵变，kJ．mol-1·K-1 △Hm 相变储能材料在熔融结晶过程中的焓