表面活性剂效用在微流系统中的变化

采用聚二甲基硅氧烷(PDMS)制作的微流芯片,研究了微流沟道中表面活性剂的效用与常规条件下的差异.结果表明,表面活性剂的临界胶束浓度(CMC)在较大的液体比表面积(表面积与体积)下,会有更大的值,说明表面活性剂的效用在不同的比表面积液体中会有不同的表现.分析其原因是表面活性剂主要作用于液体表面,在相同体积下,液体表面积增大会使得单位表面积上的活性剂减少,从而有较弱的降低界面张力的作用.

Efficiency Change of Surfactant in Microfluidic System

Utilizes the microfluidic chip made of polydimethylsiloxane(PDMS),to researchthe difference of effects of surfactant between microscale channel and ordinary condition.The resultshows that the Critical Micelle Concentration(CMC) will increase corresponded to the rise of theratio of interface area to volume,which means the efficiency of the surfactant will change with theratio of interface area to volume.The reason is that the surfactant efficiency depends on the surfactantaction on the interface,and if the liquid volume is the same,the increase of liquid surface will reducethe surfactant on unit surface area,thus has the slight effect on reducing the interfacial tension.