Particle synthesis and microencapsulation

Microfluidic structures can also be used for the high-precision processing of multi-phase systems in the form of segmented flows and unimodal emulsions, allowing the synthesis of solid materials with properties superior to those achieved by conventional processing.

Precise control of the droplet size in emulsions is used to synthesize monomodal spherical polymer particles and microcapsules which can be filled with a wide range of active ingredients during the process.

With regard to various future applications particles can be highly functionalized even during synthesis, for example by adjusting a particular porosity. The size of the polymer particles is infinitely adjustable over a broad range, e.g. between a few micrometers and several hundred micrometers.

A current field of research at Fraunhofer ICT is the increase of throughput which is attained by parallelization of microfluidic channel elements while maintaining exceptional properties regarding droplet / particle size control and dispersity.

The high precision in droplet formation also enables the formation of complex and highly regular multiple emulsions. On the basis of such emulsions polymer microcapsules can be manufactured with a solid shell approx. 100 nm thick. During the process the capsules can be filled with a well-defined amount of a solid or liquid material. Encapsulation is used for the protection, masking or transport of active core agents or other ingredients.