Science Buddies: "Ask an Expert"

Hello ! It was previously suggested to me and my group mates that we should further improve our choice of application for the oils as thermal storage to be appropriate when incorporating it within residential our building structures. Although, our concern is if the properties of the oils would change depending on the application method.

Our idea as of now is to be able to "Spray Dry" the oils as microencapsulation before incorporating them into paint for easier application especially for a large scale circumstance, rather than macroencapsulation.

Though, we are unsure if this is safe or if it will even continue to serve it's purpose, which is why we would like any additional thoughts among this matter.. Thanks a lot !

Hi

If you microencapsulate oils as phase change materials (PCMs), their underlying thermal properties(i.e., melting range and latent heat) actually don't change much, but the mode of application does matter. Spray-drying is one of the microencapsulation methods that can make the PCM easier to mix into paint in large-scale applications. The shell material itself is important: food-production spray-dry shells (such as maltodextrin) won't survive in paint. For building applications you’d need stronger shells, such as silica or cross-linked polymers, that can handle alkaline paint chemistry, resist leakage, and remain stable over time.

That said, a PCM-infused paint layer will only provide a modest amount of thermal storage because the coating is so thin—enough to smooth out small surface temperature swings, but not enough to shift room temperatures by itself. If actual building thermal buffering is the goal, a better strategy is to mix PCM paint with thicker PCM-enforced boards or plasters that have much greater heat storage capacity. Therefore, the idea of spray-dried oils within paint is feasible and safe if properly designed but as an overlay feature rather than as the storage medium itself.