Microfluidic synthesis of multiscale polymer composite particles

在下一个项目阶段，计划使用所开发的微流体辅助产生具有两级和三级组织的复合粒子的步骤来合成具有最多五级空间组织的多尺度微粒。连续微流工艺将用于有机和无机纳米粒子的集成，并将尺寸、组成和几何形状定义良好的纳米粒子组合成聚合物微粒子。采用液滴微流控和光诱导聚合、交联化的方法制备复杂的复合微粒。采用错流、Co流和流动聚焦的方法生成粒径分布较窄的单体/纳米粒子混合物液滴，并利用可控静电斥力原理确保胶体状态在纳米粒子水平上的高度稳定性。表面电荷量的控制将通过表面功能化来实现，这已在第一个项目阶段成功使用。此外，表面电荷的控制也将用于减少排斥效应的时间和有限的纳米粒子聚集。计划通过组装较小的纳米颗粒来研究这种逐步形成较大纳米颗粒的策略，以便获得更高纳米和更低微米级别的嵌套内部亚结构。尺寸在大约2到20 nm之间的颗粒的组装将被结合到亚微米范围(150到500 nm)的颗粒中，这些颗粒可以进一步整合在组成的微粒的区域中。该项目的目标是证明不同成分的分级结构的颗粒可以通过涉及微流控步骤的一般策略来产生。新的合成还应该证明，微反应技术非常适合于生成新型复合粒子。因此，该项目将通过连接纳米材料和微粒子的世界，为一般的自下而上的纳米技术战略做出贡献。同时，预计该项目将展示一种解决纳米和微米范围内组成粒子的大量组合变化的一般方法。

In the next project phase, it is planned to use the developed steps of the microfluidically assisted generation of composite particles with two and three organization levels for the synthesis of multiscale microparticles with up to five levels of spatial organization. Continuous micro flow processes will be used for the integration of organic and inorganic nanoparticles and composed nanoparticles with well-defined sizes, composition and geometries into polymer micro particles. Droplet microfluidics and light-induced polymerization and cross-linking of the polymer matrix will be applied for generation of the complex composed microparticles. Cross-flow, Co-flow and flow focusing are applied for the generation of droplets of monomer/nanoparticle mixtures with narrow size distribution.The principle of controlled electrostatic repulsion will be used for ensuring a high stability of the colloidal state at the nanoparticle level. The control of electrical surface charges will be achieved by surface functionalization which has been already successful used in the first project phase. In addition, the control of surface charge will also be used for temporal reduction of repulsion effects and for limited nanoparticle aggregation. It is planned to investigate this strategy for step-wise formation of larger nanoparticles by assembling smaller ones in order to obtain nested internal substructures at the higher nanometer and lower micrometer level. Assemblies of particles in the size range between about 2 and 20 nm will be incorporated into particles in the submicron range (150 to 500 nm) which can be further integrated in domains of composed microparticles. The goal of the project is to show that hierarchically constructed particles of different components can be generated by a general strategy involving microfluidic steps. The new syntheses should also demonstrate that micro reaction technology is well suited for generation of new types of composite particles. Thus, the project will contribute to the general bottom-up strategy of nanotechnology by bridging the world of nanomaterials and microparticles. At the same time, it is expected that the project will show a general approach for addressing the large combinatorial variety of composed particles in the nanometer and micrometer range.