“Love of beauty is taste. The creation of beauty is art”.
— Ralph Waldo Emerson
Pick up a random cream, shampoo, conditioner, foundation, mascara, or nail polish and read the ingredients. You’ll find an array of chemical names, among them many polymers.
The history of cosmetics is many thousands of years old — they existed in ancient Egypt, Greece, Rome, China, and Japan. People seem to be naturally drawn to changing their appearance, whether for esthetic or ritualistic purposes, so it’s only natural that the trend continues today in the form of a multibillion dollar industry.
Natural Origins
Originally, cosmetics and beauty products used natural plant and mineral ingredients, including castor and olive oils, aromatic oils, beeswax, rosewater, henna, carbon, gelatin, egg whites, safflower, and rice powder. Natural makeup was used to some extent on every continent until the 20th century when — Influenced by the movie industry — the mass production of cosmetics began. The simultaneous development of the chemical industry made synthetic components an indispensable part of the cosmetics industry. Polymers for Personal Care and Cosmetics, summarizing the ACS meeting in 2012, said:
Polymers are routinely used in many personal care and cosmetic products. The applications take advantage of the various properties of these polymers to impart unique benefits to their formulations. The range of properties is as varied as the class of polymers that have been utilized. Using polymers, cosmetic chemists can create high performance products. Broad spectrums of polymers; natural polymers, synthetic polymers, organic polymers as well as silicones are used in a wide range of cosmetic and personal care products as film-formers, emulsifiers, thickeners, modifiers, protective barriers, and as aesthetic enhancers.
How Are Polymers Used?
Thickeners
Let’s take a closer look at the polymers used in cosmetics nowadays. Water-based formulations are often quite fluid in nature, and polymers are used to change their rheology, i.e., to increase viscosity, thicken, or gel them. Natural polymers such as starch, starch, xanthan or guar gum, carrageenan, alginates, polysaccharides, pectin, gelatin, agar, and cellulose derivatives can be used to this end. On the synthetic side, polyacrylate derivatives and polyacrylamide polymers are most popular for this purpose. More recent developments include combining hydrophobic and hydrophilic polymers into block and star copolymers and thermally responsive systems.
Structuring Agents
Structuring agents that add rigidity include natural and synthetic waxes, lanolin, long-chain fatty alcohols, and triglycerides. A popular component, poly-alpha-olefin, does not feel greasy and is used in products like eye shadows and lip products. Glycol stearates serve as opacifiers and add a pearlizing effect. Polyurethanes are used in nail and mascara products because they form strong films.
Hair Products
Hair products typically use cationic polymers, since hair is negatively charged. Natural products include polysaccharides, such as starch and cellulose derivatives, natural gums, and hydrolyzed proteins. Synthetic hair-friendly polymers include polyvinyl pyrrolidone and acetate, polyvinylamides, polyacrylates and polymethacrylates, polyurethanes, and silicones.
Delivery Systems
Polymers can serve as delivery systems for active cosmetics components, such as antioxidants and antimicrobials. Natural antioxidants, such as vitamins C and E, grape seed extract, horse chestnut extract, and celery or cucumber extracts are used, along with synthetic extracts like butylated hydroxyanisole or butyl hydroxyl toluene. Polymer carriers can physically entrap the active component, preserving its biological stability, or the bioactive component can be incorporated chemically into a polymer chain or pendant group, then released through hydrolysis. For example, salicylic acid (an anti-acne ingredient) can be incorporated into the main chain of polyanhydride ester and released within a short time.
The Latest
There is a lot of polymer innovation going on in cosmetics. One of the latest ideas is 3D makeup printing, which allows you to create your own custom-color makeup using the Mink printer and FDA-approved polymer ingredients. According to Heidi Milkert, writing on 3DPrint.com:
By keeping the printer itself affordable at around $300, and the ink, as well as makeup substrate at commodity prices, she [Mink founder Grace Choi] hopes to launch with a bang. What this could mean for the makeup industry is almost unfathomable.
Image by vnlit/123RF.
Source: “Polymers for Personal Care and Cosmetics: Overview,” by A. Patil and M.S. Ferritto, a chapter in Polymers for Personal Care and Cosmetics, ACS Symposium Series; American Chemical Society: Washington, DC, 2013, pp. 3-11. doi: 10.1021/bk-2013-1148.ch001.
Source: “The Mink 3D Makeup Printer Will Print Colorful Lipstick, Eye Shadow, and More,” by Heidi Milkert, 3dprint.com, May 5, 2014.