采用直接原位聚合法制备了以石蜡为囊芯的脲醛树脂微胶囊,并利用激光粒径分布仪、X射线衍射仪、差示扫描量热仪(DSC)和傅立叶转换红外光谱仪分别分析了微胶囊的粒径分布、热稳定性、热焓值和壳结构。结果表明,所得微胶囊粒径分布均匀,并具有良好的热稳定性和较高的相变潜热;影响石蜡微胶囊相变潜热和平均粒径的主要因素包括芯壁材料比、搅拌速度、温度、系统改性剂PVA(聚乙烯醇)用量等;最佳工艺条件为囊壁比0.78:1,反应温度70℃,搅拌速率2500r/min,系统改性剂PVA用量0.26g,pH=2.0-3.0。
A urea-formaldehyde colophony microcapsule containing the paraffin as the core material was prepared by in-situ polymerization method without prepolymerization.The diameter distribution,the thermal stability,the enthalpies and the structure of the microcapsules were analysed by the laser particle size analyzer,X-ray diffractometer,DSC and FT-IR,respectively.The results show that the microcapsules obtained by the method in the paper is symmetrical on the diameter distribution,smooth on the surface,and steady on the thermal character;the main parameters influencing the average diameter and the enthalpies of the microcapsules contained the rate of the core and the shell material,the reactive temperature,the stir rate,the dosage of the system modifiers;the optimized parameters for microcapsule production are as follows: 0.78∶1 for the mass ratio of core material to shell material,70℃ for the reactive temperature,2500 rpm for the stir rate,0.26g for the dosage of the system modifiers,2.0-3.0 for pH value.