Abstract: TiO2 nanoparticles are easy to aggregate during the preparation and use because of their strong surface effects. It is a key problem for the application of TiO2 nanoparticles in refrigerating system. The stability of TiO2 nanoparticles in refrigerants was systemically investigated with sedimentation, light transmission ratio index measurement and means of particle size distribution measurement in this work. It has been revealed that the stability of TiO2 nanoparticles in refrigerant is better, and the polarity and dielectric constant of refrigerant are the main factors. Surfactant Span-80 might act as a dispersant in refrigerant. The effect of temperature on the stability was significant. The results will provide the basic data for the application of TiO2 nanoparticles in refrigerator.

Key words: nanoparticle, refrigerant, particle size, surfactant, temperature

摘要： 纳米TiO2颗粒在制备和应用过程中极易团聚，解决其分散问题是纳米TiO2颗粒在制冷系统中应用的基础和前提. 本工作利用目测沉降观察、分光光度计吸收测量法和激光粒度分析法，实验研究了纳米TiO2颗粒在制冷工质中的分散特性. 结果表明，纳米TiO2颗粒在制冷剂中分散较稳定，制冷剂介电常数和极性是主要的影响因素；Span-80可以作为纳米TiO2颗粒在制冷剂中的分散剂；温度对纳米TiO2颗粒在制冷剂中的分散稳定性影响明显. 研究结果可为纳米TiO2颗粒在制冷系统中的应用研究提供基础数据.

关键词: 纳米颗粒, 制冷剂, 颗粒粒度, 表面活性剂, 温度