The Science Of Scrubs!
We might be biased, but here at the Haus we really love our scrubs - there are few things better than feeling clean and smelling great. But have you ever wondered exactly how they work? And what exactly is the difference between soaps and detergents?
LIke many of the scientific developments of the 20th century, the creation of modern detergents was an unexpected product of supply shortages during both World Wars. The shortage of natural oils that are commonly used to make traditional saponified soap led industry chemists to develop a range of artificial substances that mimicked the cleaning properties of oil based soap. During these early years, most of the ingredients in detergent products were petroleum derived, helping to lead to their less than stellar reputation amongst consumers.
Today, however, we are fortunate that most of the common ingredients in detergents are derived from coconut or other naturally occuring fats, so it is possible to source more ethical components.
While it might sound strange to say "liquid hand detergent" or "whipped detergent", that's exactly what these products are! In fact, most of the "soaps" that are sold in stores are actually detergents.
So how do detergents work? Do they function differently from natural soaps?
Detergents work to clean dirt and oils in much the same way that natural soap does - by introducing a chemical that reduces the surface tension between water and non-soluble compounds such as oil. This is achieved by using a surfactant, generally the most important ingredient in a detergent or scrub. A surfactant is a compound whose molecules are water bond forming on one end and oil bond forming on the other. Their ability to interface with both types of chemicals is what makes surfactants the life of the party.
Schematic diagram of of oil in aqueous suspension, such as might occur in an emulsion of oil in water. In this example, the surfactant molecules' oil-soluble tails project into the oil (blue), while the water-soluble ends remain in contact with the water phase (red).
By reducing surface tension, surfactants make it possible to remove dirt and grease from skin and surfaces. This emulsifying process is what creates all the lovely lather that makes our scrubs and whipped soaps a delightful way to start your day. As an added bonus, detergents don't form soap scum in hard water.
Due to the more alkalyne nature of soaps, they have a tendency to react with ions of Magnesium and Calcium in tap water. In areas with soft water, natural soaps can be used without having to worry about much buildup, the mineral content of many cities' water systems creates a precipitate when interacting with traditional soaps. The resulting material is non-soluble and practically impossible to remove if you've ever been unlucky enough to try.