Silicones have many unique properties that make them a preferred ingredient for hair care product formulators. They form a film on the surface of hair strands which allows them to effectively act as a lubricant between adjacent hair strands and reduce the forces required for detangling hair. Due to their high refractive index, they also impart a high degree of gloss and shine to hair when used in conditioners and styling products. Silicones also provide protection from the thermal damage often sustained during hair drying and heat styling. Certain silicones, especially amine-functionalized ones, have also been shown to increase color retention of artificially dyed hair.
However, despite their numerous benefits, curlies are frequently admonished to minimize use of silicones or to avoid them entirely.
So what's the problem?
Sadly, there can be too much of a good thing. Years ago, it was fashionable for stylists to douse curly hair in heavy silicone oils in order to get control of frizz and to add a much-coveted shine to curls. Unfortunately, these products had a tendency to backfire over time. With repeated use, the serums accumulated on the surface of the hair, keeping water from entering the cortex and causing it to become dehydrated, weighing down hair, and completely disrupting natural curl pattern. The buildup could be very difficult to remove, requiring repeat applications of harsh shampoos. The result was dry, frizzy hair that resisted attempts to restore its natural beauty.
Similar results can occur when conditioners with high amounts of non-water soluble dimethicone are used. Buildup issues are especially problematic when non-traditional methods of cleansing are employed, such as conditioner cleansing, baking soda scrubs, or vinegar rinses. For this reason, it has become a popular recommendation for curly-haired people to avoid products containing silicones. This has the unfortunate consequence of depriving many curlies of some of the beneficial properties of silicones in hair care products.
Is There a Solution?
Happily, polymer chemists have spent time developing and optimizing water soluble silicone-based polymers for various reasons. These materials impart many of the desirable properties of ordinary silicone polymers, but they are more easily removed from the hair via rinsing, conditioner washing, or cleaning with mild shampoos, and do not require the use of harsh sulfate-based surfactants. They can also enhance moisturizing properties or add humectant qualities. These silicones provide more options to curly ladies and gentlemen.