SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2020, Vol. 28 ›› Issue (5): 1368-1374.DOI: 10.1016/j.cjche.2019.12.010

• Chemical Engineering Thermodynamics • Previous Articles     Next Articles

A novel approach to study the interactions between polymeric stabilized micron-sized oil droplets by optical tweezers

An Chen1, Shaowei Li2, Jianhong Xu1   

  1. 1 The State Key Lab of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China;
    2 Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
  • Received:2019-09-17 Revised:2019-12-07 Online:2020-07-29 Published:2020-05-28
  • Contact: Shaowei Li, Jianhong Xu
  • Supported by:
    The authors gratefully acknowledge the supports of the National Natural Science Foundation of China (21476121, 21322604) for this work.

A novel approach to study the interactions between polymeric stabilized micron-sized oil droplets by optical tweezers

An Chen1, Shaowei Li2, Jianhong Xu1   

  1. 1 The State Key Lab of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China;
    2 Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
  • 通讯作者: Shaowei Li, Jianhong Xu
  • 基金资助:
    The authors gratefully acknowledge the supports of the National Natural Science Foundation of China (21476121, 21322604) for this work.

Abstract: The well understanding of interaction forces between single dispersed droplets is crucial to the understanding of emulsion stabilization mechanism. Recently, many studies have reported the direct quantitative measurements of interaction forces between 20-200 μm single droplet coated polymers by atomic force microscope (AFM). These studies have revealed many important results about the relationship of the interaction forces and the droplet deformation. However, these studies of the quantitative relationship between the measured interaction forces and the separation distance of the front end of the droplet have rarely been reported. Optical tweezer instrument can make it possible to establish the quantitative relationship between the measured force and the separation distance of the front end of the droplet, which will make better understanding of the interaction mechanisms between droplets. Due to the differences of the measuring mechanism between atomic force microscopy (AFM) and optical tweezers, the theory model of AFM measurements cannot be fitted with the force measurement by optical tweezers. We have made an exhaustive comparison of the measuring differences between AFM and optical tweezer instrument in this work. Moreover, we built a numerical model to derive the repulsive pressure through the measured force curve in order to quantify the measured force of two micron-sized oil droplet coated polymers by optical tweezers. Furthermore, the novel method can be extended to other micron-sized emulsion systems, and these findings will be a vital progress on quantitative force measurements between micron-sized droplets.

Key words: Emulsions, Stabilization mechanism, Interactions, Polymers, Optical tweezers

摘要: The well understanding of interaction forces between single dispersed droplets is crucial to the understanding of emulsion stabilization mechanism. Recently, many studies have reported the direct quantitative measurements of interaction forces between 20-200 μm single droplet coated polymers by atomic force microscope (AFM). These studies have revealed many important results about the relationship of the interaction forces and the droplet deformation. However, these studies of the quantitative relationship between the measured interaction forces and the separation distance of the front end of the droplet have rarely been reported. Optical tweezer instrument can make it possible to establish the quantitative relationship between the measured force and the separation distance of the front end of the droplet, which will make better understanding of the interaction mechanisms between droplets. Due to the differences of the measuring mechanism between atomic force microscopy (AFM) and optical tweezers, the theory model of AFM measurements cannot be fitted with the force measurement by optical tweezers. We have made an exhaustive comparison of the measuring differences between AFM and optical tweezer instrument in this work. Moreover, we built a numerical model to derive the repulsive pressure through the measured force curve in order to quantify the measured force of two micron-sized oil droplet coated polymers by optical tweezers. Furthermore, the novel method can be extended to other micron-sized emulsion systems, and these findings will be a vital progress on quantitative force measurements between micron-sized droplets.

关键词: Emulsions, Stabilization mechanism, Interactions, Polymers, Optical tweezers