Cleaning products contain surfactants that form micelles when reaching a critical concentration. Micelle formation is affected by factors such as temperature, atmospheric pressure, and other surfactants. Computer-controlled instruments and laboratory software are used to measure micelle concentration. The properties of surfactants can be plotted to determine rates of change.
Cleaning products usually contain surfactants or particles that act as active agents on the surface of the water. The molecules are structured with a head that is attracted to the water, while the tail is repelled by it. This tail sticks to oil and grease and can suspend dirt in an aqueous solution. When these particles reach a density on the surface where they can no longer fit, this is typically called the critical micelle concentration. A micelle is a spherical or elliptical structure formed when surfactant molecules stick together and the heads gather at the surface while the tails point inward.
The critical concentration of micelles is a measurement that can help determine when surfactants will form these structures. Factors that can be used to predict micelle formation include surface tension. The tension at the water surface typically decreases with a higher concentration of surfactants. The particle concentration and surface tension variables can be graphed to provide a visual clue to the mathematical beginning of the critical micelle concentration. Computer controlled instruments and laboratory software are often used to check solutions and take these measurements.
Other factors that can affect the critical concentration of the micelles are temperature, atmospheric pressure and other surfactants in the solution. Micelles generally only form above a certain temperature. The micellar concentration of sodium dodecyl sulfate in water, for example, is typically 77°F (25°C) if no other compounds are added. Fewer parts of the surfactants rejected by the water are exposed, usually by reducing the energy and surface tension of the fluid.
Once the critical micelle concentration is reached, any surfactant added generally forms micelles immediately. The conductance and photochemical properties of a solution can also affect the point of micelle formation, but how the solution is measured can affect these and therefore the critical micelle concentration. It is usually important to know how many surfactant molecules are at the surface interface and how many remain in bulk. Sometimes air bubbles rising to the surface can disturb the interface and reduce the overall surfactant concentration.
The properties of surfactants can be plotted to determine rates of change. Within a certain range the concentration can be found; this is often accomplished through experimentation and mathematical calculation. The reverse measurement can often be performed, which can be useful at low surfactant concentrations and when there are large amounts of solvent.
Protect your devices with Threat Protection by NordVPN
