渗透诱导结构演化的微流控双重乳液为模板合成聚合物微颗粒的研究

Template synthesis of polymeric microparticles from microfluidic double emulsions with osmosis-induced structural evolution

利用渗透压诱导的水分子跨界面传质过程实现了双重乳液尺寸和结构的调控,并将可控演化的双重乳液液滴作为模板,可控制得到中空结构、孔壳结构等多种结构的功能微颗粒。利用微流控技术产生均一尺寸的双重乳液,通过在双重乳液内部液滴和外部水相中采用不同盐浓度来构建渗透压差,使得双重乳液在渗透压差驱动下经水分子跨界面传质发生收缩/膨胀过程,实现对双重乳液尺寸结构的演化和调控,推导了其在演化平衡时内部水滴尺寸的计算公式。利用不同演化阶段的双重乳液为模板,成功制得了具有中空结构和孔壳结构且壳层具有多孔结构的聚合物微颗粒。该研究为新型聚合物微颗粒的设计和可控构建提供一种有效策略。

The regulation of the size and structure of double emulsions is realized through osmosis-induced trans-interfacial mass transfer of water molecules.Versatile microparticles with hollow and hole-shell structures can be obtained controllably by using the controllably evolved dual lotion droplets as templates.Microfluidic technique is used to generate double emulsions with uniform sizes.Different salt concentrations are employed in both the inner water droplet and outer continuous water phase of double emulsions to create an osmosis difference to drive the shrinking and expanding evolution of double emulsions via osmosis-induced trans-interfacial mass transfer of water molecules.Such processes realize the evolution and control of the size and structure of double emulsions.An equation is derived to predict the size of the inner droplets in double emulsions at equilibrium evolution state.Moreover,using double emulsions at different evolution states as templates,polymeric microparticles with hollow and hole-shell structures containing a porous shell are successfully fabricated.This work provides an effective strategy for design and controllable fabrication of novel polymeric microparticles.