Non-spherical particle production advances

The team published their innovations in the Journal of Colloid and Interface Science under the title, Getting in shape: Molten wax drop deformation and solidification at an immiscible liquid interface. 

Particle profiles​
Four particle shapes were reliably reproduced during the study: ellipsoid, mushroom, flake-like, and disk. These and other novel shapes could make new formulation strategies and ingredient delivery concepts possible. In part because shape governs how densely particles pack together as well as the volume and character of surface area each given particle has.

Promising technique​
Professor Shen and the team worked with wax but predict that polymeric and hydrogel materials, responsive to temperature, could be manipulated with the same method, according to an article on azom.com​, a materials science site.

“People have done studies similar to this in the past using liquid metals impacting solid surfaces, but not other liquids. In terms of the fundamental physics, I believe this research is unique,” ​Professor Shen told azom. “In terms of applications it’s also very important because of how simple and low cost this method is as well as how easily it can be scaled.”​

What’s happening​
The article in the Journal of Colloid and Interface Science reviews “the deformation and simultaneous solidification of millimeter size molten wax drops as they impacted an immiscible liquid interface of higher density,”​ according to the abstract. “By varying initial temperature and viscoelasticity of the molten drop, drop size, impact velocity, viscosity and temperature of the bath fluid, and the interfacial tension between the molten wax and bath fluid, spherical molten wax drops impinged on a cooling water bath and were arrested” ​to form the four shapes described above.

Applications​
Advances in particle-level technologies often have applications for scientists across industries. This and other recently published processes are applicable in and beyond cosmetics and pharmaceuticals.

Korean scientists only just developed a machine to mix oil and water without surfactants, according to Cosmetics Design​. “Our technology is the only one that can mix​ water and oil at room temperature without using surfactants,” explained Dr. Choo Min-chul of the Korea Research Institute of Standards and Science. “The method can be utilized in not only body-friendly cosmetics but also drugs or food. So, our achievement can exert a huge impact on the industry and society in general.”​