粘度在液滴尺寸的应用

摘要尺寸的灵活调节是微流控芯片液滴的一大特色，于微纳材料合成具有重要意义。对于正向压力驱动的液滴形成方式来说，采用流体流速调节液滴尺寸是一种行之有效的方法，但对于负向压力驱动的液滴形成方式而言，连续相和分散相由一个共同的负压驱动，两相的流速不能单独调节，流速调节无法有效调控液滴的尺寸。为解决此问题，我们建立了一种简单的基于连续相粘度变化的液滴尺寸控制技术。通过调节高粘度油相（矿物油）和低粘度油相（十六烷）的比例，我们获得了一系列不同粘度的混合油。在排除通道尺寸、表面张力、流体流速等因素的影响下，以不同粘度的混合油为连续相，以0.1%的亚甲基蓝水溶液为分散相，实现了不同大小的液滴形成，从而证明了油相粘度的调节可作为一种简单有效的调控液滴尺寸的方法，可用于负压驱动的液滴形成，从而减少注射泵的使用数量，有利于实现高通量的液滴合成或者液滴筛选。50697

该论文有图5幅，表1个，参考文献13篇。

毕业论文关键词：微流控芯片液滴黏度表面张力

The Application of Viscosity on the Droplets Sizes Control

Abstract

The flexible adjustment of droplets size is one feature of droplet microfluidics, which has great significance in micro/nano materials synthesis. For droplets formation driven by positive pressure, the droplets sizes are main regulated by varying fluid velocity. But for droplets formation driven by negative pressure, the continuous phase and the dispersed phase are driven by the same negative pressure, and the flow velocities of these two phases can't be adjusted alone. In this case, the velocity regulation is not effective for droplets size variation. To solve this problem, we developed a simple method to control droplets size via changing the viscosity of the continuous phase. By adjusting the proportion of the high viscosity oil phase (mineral oil), and low viscosity oil phase (hexadecane), we obtained a series of mixed oil phases with different viscosities. After eliminating the influence of channel sizes, surface tension, and flow rate, we used mixed oil phases with the different viscosity as continuous phase and 0.1% (wt) methylene blue aqueous solution as the dispersed phase, to form droplets. The size of droplet decreased with the viscosity rising of the mixed oil phase, which proved that the viscosity adjustment of the oil phase was a simple and effective method to regulate the droplets sizes. This method can be used to form droplets in the negative pressure driven style, and minimize the use of injection pumps. It is also beneficial to generate large quantity of droplets for high throughput screen or materials synthesis.

Key Words: Microfluidics Droplet Viscosity Surface tension

摘要Ⅰ

Abstract-Ⅱ

目录Ⅲ

图清单-Ⅳ

表清单-Ⅳ

变量注释表-Ⅳ

1 绪论1

2 实验部分2

2.1材料及仪器 2

2.2芯片制作及表面修饰2

2.3粘度的测定 2

2.4表面张力的测定 3

2.5液滴的形成及调节-3

3 结果与讨论-3

3.1油相组成对运动粘度的影响-3

3.2油相组成对表面张力的影响-5

3.3油相组成对液滴尺寸的影响-5

4 结论-7

参考文献-8

致谢-9

图清单

图序号图名称页码

图3-1 油相运动粘度与其组成的关系图 4

图3-2 具有不同运动粘度的油相的表面张力测定结果统计图粘度在液滴尺寸的应用:http://www.youerw.com/huaxue/lunwen_54070.html