Green Chemistry Concepts in Personal Care and Cosmetics

Posted: February 14, 2008

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A polysaccharide to replace petrochemicals: Montana Polysaccharides Corp. suggests levan, a multipurpose exopolymer, as a raw material to replace petrochemicals in certain personal care products and in the products of many other industries. This polymer of fructose has an extremely low intrinsic viscosity so that it requires less energy to handle, does not swell in water, is heat- and acid-stable, and causes no skin or eye irritation, even on prolonged, direct contact. Unlike products from corn, soy, and waste biomass that require significant amounts of energy and solvents for separation from cells, levan is naturally exported from producing cells, so it is a cost-effective raw material. Levan can be derivatized to make powerful surfactants.

Thioglycolic acid from green chemistry: Arkema Inc. uses a green chemistry to manufacture thioglycolic acid (TGA or mercaptoacetic acid) without using hydrogen sulfide (H2S) as a feedstock. H2S is a poisonous, flammable, colorless gas that is regulated as an air pollutant, a water pollutant and a hazardous waste. Arkema replaced the H2S in its manufacturing process with sodium hydrosulfide (NaSH). NaSH is safer for workers, is subject to fewer air, water, and waste regulations, is comparable to H2S in price, and is readily available in consistently high purity. TGA is used in hair waving formulations.

A solventless process for making tackifiers and adhesives: The Argonne National Laboratory at the US Department of Energy developed a process to make tackifier dispersions for pressure-sensitive adhesives (PSAs) used in cosmetics, personal hygiene and many other industries. Traditionally, PSAs were made by combining tackifier dispersion with latex dispersions. Preparation of the tackifier dispersions typically involved organic solvents for dissolving high temperature resins. During subsequent heating to evaporate and recover excess solvent, some solvent emissions occurred; over time any residual solvents in the adhesive also evaporated into the environment.

The Argonne process pulverizes the resin to an average particle size of less than 5 μm and then directly forms the dispersion in water, in just a few minutes, without dissolving the resin in solvents, melting it or using excess water. The process does not require solvents or heat to process either high- or low-temperature resins. Argonne’s process is cost-effective and energy-efficient. It reduces the cost of manufacturing water-based tackifier dispersions by more than 35% and uses less than 25% of the energy required by conventional processes, thereby reducing greenhouse gas emissions.

Biosurfactants to replace petroleum-derived surfactants: Jeneil Biosurfactant Co. developed biobased surfactants that are less toxic and more biodegradable than conventional petroleum-based surfactants.