纳米二硫化钼对冷冻机油密度和黏度的影响

Influencese of molybdenum disulfide on density and viscosity of nanorefrigeration oil

采用聚乙烯吡咯烷酮（PVP-K30）对纳米二硫化钼（MoS2）进行表面化学修饰，配制了分散稳定性良好的环烷基纳米冷冻机油。利用旋转式黏度计和密度仪对5种配比的纳米冷冻机油（二硫化钼质量分数为0.25%、0.5%、0.75%、1%、1.25%、1.5%）在不同温度（288~333K）下的密度和黏度进行了测试，并对其数据进行了拟合关联。实验结果表明：经 PVP 修饰的纳米 MoS2在低浓度情况下在冷冻机油中分散稳定性能良好，且在质量分数之比为1∶1时达到最佳分散效果；纳米冷冻机油的黏度随MoS2和PVP质量分数的增加而下降，在温度较低时更为明显；纳米冷冻机油的密度测量值和计算值基本吻合，其密度黏度关联式的计算值与90%的实验数据吻合较好。该结果为纳米冷冻机油在传热、流动和摩擦领域的应用提供了重要的基础数据。

In this research,the nanofrigeration oil with good stability were prepared by adopting polyvinylpyrrolidone （PVP-K30）to modify molybdenum disulfide nanoparticles. Tests on the density and viscosity of 5 nanorefrigeration oil with different proportions（mass fraction of molybdenum disulfide is 0.25%,0.5%,0.75%,1%,1.25%,1.5%,respectively）were carried out using rotating viscometer and densimeter within the temperature range of 288K to 333K. Based on the experimental results , data-fitting was done correspondingly. The experimental results showed that：MoS2 nanoparticles had good dispersion stability in low concentration nanorefrigeration oil after modified by PVP. The nanorefrigeration oil presented the best dispersion performance when mass fraction proportion of MoS2 and PVP was 1∶1;with the increase of mass fraction of MoS2 and PVP,the viscosity of nanorefrigeration oil decreased and the reduction was more obvious in lower temperature conditions;the measured values of density of nanorefrigeration oil were basically consistent with the calculated values,and 90 percent of the values calculated from viscosity-density correlation agreed with the experimental data. The results of the research provided important data foundation for application of nanorefrigeration oil in fields of heat transfer,flow and friction.