Textured Microcapsules through Crystallization
Professor Stefan A. F. Bon -  Department of Chemistry at Warwick University

Presentation - pdf

Abstract: In this talk we will shortly introduce some of our innovations towards greener formulations in personal care. The main focus of the talk will be on our recent work in which we demonstrate the fabrication of surface textured microcapsules formed from emulsion droplets which are stabilized by an interlocking mesh of needle-like crystals. Crystals of the small organic compounds are formed within the geometric confinement of the droplets. Microcapsule diameter can be easily tuned using microfluidics. This approach also proves to be scalable when using conventional mixers, yielding spikey microcapsules with diameters in the range of 10-50 µm. The capsule shape can be molded and arrested by jamming using recrystallization in geometric confinement. We will show that these textured microcapsules show a promising enhanced deposition onto a range of fabric fibers. More information: https://bonlab.info


Stefan A. F. Bon is a full professor in the Department of Chemistry at the University of Warwick (UK). His research team, BonLab (https://bonlab.info), combines polymer and colloid chemistry with soft matter physics and adds a chemical engineering twist to innovate in science. He has graduated over 25 PhD students on projects in close collaboration with a variety of industrial partners, and has published > 100 scientific papers.

Q&A (answered in chat)

Q. How scalable is the process of making these capsules?

A. Technology is scalable as can be used with standard blenders

Q. maybe a silly question, but with making particles "spiky" is there any potential for enhanced irritation potential? perhaps more likely to damage membranes in the body?

A. Not sure, the spikes are on the order of a few micrometer or less. Clearly the crystal shape may have an influence. The same would hold for microcrystalline cellulose (needle like).

Q. Could an application of those spikey microcapsules be in the laundry industry, where encapsulated perfumes have been used lately?

A. I think we can encapsulate fragrance if we use high T processing in a closed system, high T being emulsification at 80-90 C

Q. Is this encapsulation process then restricted to delivering non-volatile actives.  So fragrances would be excluded?

A. I think we can encapsulate fragrance if we use high T processing in a closed system, high T being emulsification at 80-90 C

Q. Do the spikey capsules have interesting rheology properties compared to the smooth particles.

A. Rheology definitely is interesting…higher solids dispersions would be good to look at if there is any interesting behaviour