Researchers from Binghamton University conducted research that could lead to more environmentally friendly paints and coatings. The new research focuses on using Janus particles in paint.

Janus particles are dual in nature and they are engineered to have two surfaces with distinct physical properties. One side is hydrophilic or attracted to water, and the other side is hydrophobic, or water repellent. Janus particles couldn’t be produced in large quantities with unclear commercial applications. The team found that these particles could be the key to create environmentally friendly paint and coatings.

Microscopic Janus particles are illustrated on the cover of the August edition of Materials Horizons. Source: Materials Horizons

Previous studies on Janus particles focused on structures formed by the particles at a small surface scale. The new study focuses on using these particles to improve the performance of paint and coating.

There are a few options in a typical painting process. A popular option is to use a primer layer then a paint layer, but this is time-consuming. Another option is to mix paint with solvents, but solvents are a health risk and their fumes are a problem in small spaces. A third option is water-based paints, but those still contain solvents and may not be as durable.

To test Janus particles in paint, the team mixed hydrophilic and hydrophobic Janus particles with commercial paints and painted surfaces to see how particles react. The results were interesting. The hydrophilic side oriented to the surface and helped coatings adhere to the surface better. The hydrophobic side, faced towards the surface, made the paint water repellent. The particles diffused and arranged themselves into self stratifying layers more quickly and in ways that didn’t completely fit the team’s hypothesis. There is no theory that explains self-stratification behaviors.

Researchers say that further research is needed to fully understand the principles of Janus particles. Once they are fully understood, researchers can move to design the next generation of environmentally friendly smart coating materials.

A paper on this research was published in Materials Horizons.