采用“两步法”制备了TiO2-H2O 悬浮液,通过添加分散剂十二烷基硫酸钠(SDS)来提高悬浮液的稳定性.对不同 SDS 浓度下 TiO2-H2O 悬浮液的粒径大小、zeta电势、吸附量、颗粒浓度和导热系数进行了测试,研究了SDS对TiO2-H2O 悬浮液稳定性和导热性的影响.结果表明,添加适当浓度的分散剂能显著提高悬浮液的稳定性,从而增强其导热性能.在实验中,SDS浓度为0.35%(质量分数)时,0.7%(质量分数)的TiO2-H2O 悬浮液的稳定性和导热性最好.分散剂通过影响纳米颗粒的尺寸、吸附量和颗粒浓度,来影响悬浮液的导热系数,SDS 的吸附量越大,TiO2颗粒悬浮浓度越低,TiO2-H2O 悬浮液的导热系数越小.
TiO2-H2O suspensions were prepared by two-steps method,which used surfactant sodium dodecyl sulfate (SDS)to enhance the stability.By means of measurement of particle size,zeta potential,adsorbing ca-pacity,particle concentration and thermal conductivity at different SDS concentration,the effects of SDS on the stability and thermal conductivity of TiO2-H2O suspensions were studied.The experimental results show that there was an optimizing surfactant concentration corresponding to the best of stability and thermal conductivity of suspensions,in the present study,the 0.35wt% SDS can be regarded as an optimal concentration to obtain the best stability and the highest thermal conductivity for the 0.7wt% TiO2-H2O suspension.Surfactant could influence the particle size,adsorption quantity and particle concentration,thus influenced the thermal conduc-tivity of suspensions.The thermal conductivity of TiO2-H2O suspension would decrease with increased the ad-sorption quantity of SDS and decreased the concentration of TiO2 particles.