Nonionic surfactants belong to the different types of surfactants that are used in detergents. They, along with other surfactant, play a big role in how a detergent works to clean and dissolve dust, stains, and dirt from our clothing and fabrics.
Before understanding what nonionic surfactants are, you first of course need to understand the basics of surfactants in general first. Basically, a surfactant is a substance that acts to lessen the surface tension of a liquid when it’s mixed in with that particular liquid. In the case of detergents, the liquid is obviously water. You see, water, by itself, is woefully inadequate as a washing and cleaning agent that can remove dirt and tough stains. This is why detergents are needed. The surfactants in the detergent –these ingredients differentiate a detergent from regular soap – act to lower the surface tension of the water, which makes it “wetter”, allowing it so soak and interact with the dust, stains and dirt embedded in the fabric.
Surfactants work through adsorption, which is a process where a film of atoms and molecules is built up on the surface of the liquid – you’ll see this thin film covering water mixed with detergent – which is the one responsible for reducing the water’s surface tension.
Surfactant types are differentiated by the charge they carry. The negatively charged surfactants are called anionic surfactants, which, while effective against dirt and oily stains, suffer from reduced effectivity in hard water. Hard water is water with calcium and magnesium content – the more of these there are, the less effective the surfactant will be. Cationic surfactants also remove stains, but are primarily used in fabric softeners or detergents with built in fabric softeners. Surfactants with combined positive and negative charges are called Amphoteric or zwitterionic surfactants. Nonionic surfactants, on the other hand, are neutral, meaning they have no charge. They are mixed in with detergents to minimize the effects of hard water and keep the detergent as effective at cleaning as possible.