Carbomer is utilized in a wide variety of cosmetic and personal care products, pharmaceuticals and household cleaners. Most Carbopol polymers are high molecular weight acrylic acid chains usually crosslinked and are available as powders or liquids. In the cosmetic industry, Carbomer is used as a thickener in lotions, creams and gels. It is also used to stabilize, suspend, and control the release of pharmaceutical products. At low concentrations, suspensions flow easily with a slippery feel. At higher concentrations, high viscosity varieties form gels that are pseudoplastic. At rest, the batch has a very high viscosity and resistance to flow. When shear force is applied by a mixer or pump, the apparent high viscosity is reduced.
The typical powder is very light and fluffy, forming clouds of airborne dust if not handled carefully. It tends to float on water, requiring a good vortex to wet out. Once wet, it swells quickly creating high viscosity. Different varieties produce varying viscosities, but most are used below 1% concentration. The crosslinked polymers are not actually water soluble, but swell into hydrated spheres that give the product its rheological properties.
There are many different types of Carbomer, the difference between them is 940 used a benzene chemistry crosslinking agent while the 980 crosslinker is benzene free and therefore deemed cleaner.
There are many different types of cross linked polyacrylate thickeners on the market and they are mainly used to thicken up and give suspending power (so that the product can hold beads or actives) to gels, lotions and creams. This version is popular as it can be used in clear gels, has good thickening power and is an excellent suspending agent. It is supplied as a powder and requires some time to fully wet and swell in the water phase. Additionally, the polymer requires neutralizing to enable it to fully swell. This is done with an alkali such as sodium hydroxide and only a tiny amount is needed. This is usually added at the end of manufacturing so that you don't trap air into the mix when stirring.
Use between 0.1-1.5% in a formulation. This thickener is not compatible with high levels of salt or for high surfactant containing formulations.
For people looking to use this to thicken high strength alcohol gels we recommend neutralising with Triethanolamine (TEA) rather than Sodium Hydroxide solution.
