Synthetic hair comes from petroleum-based plastic polymers, primarily acrylic, polyester, and nylon. These raw materials start as small plastic pellets in a factory, then get heated, melted, and pushed through tiny holes to form the fine strands that mimic human hair. The entire process is industrial chemistry, turning crude oil derivatives into something soft enough to braid, curl, or weave.
The Raw Materials
In its most basic form, synthetic hair is low-grade acrylic that has been heated and strung into strands. Most products on the market use a blend of three common polymers: acrylic, polyester, and nylon. All three originate from petrochemicals, meaning they trace back to refined crude oil or natural gas. These polymers are chosen because they can be engineered to feel soft, hold color well, and resist tangling, properties that make them passable substitutes for human hair at a fraction of the cost.
The specific blend varies by brand and product type. Some fibers lean heavier on acrylic for a natural texture, while others incorporate more polyester for durability or shine. Chemical coatings are often applied to the finished fibers to reduce friction and tangling, though these coatings (which can include alkaline compounds, plastics, and other additives) are also the main source of the scalp irritation some people experience with new synthetic hair.
How Synthetic Hair Is Made
The manufacturing process is called melt spinning, and it works roughly the same way for most synthetic fibers. Polymer pellets, small chunks of solid plastic, are fed into a screw extruder, which is essentially a heated barrel with a rotating screw inside. The combination of heat and mechanical pressure melts the pellets into a thick liquid.
That molten polymer is then forced under pressure through a spinneret, a metal plate perforated with dozens or hundreds of tiny holes. Each hole produces a single continuous filament. Think of it like a pasta machine, but operating at much higher temperatures and producing strands far thinner than spaghetti. As the filaments emerge from the spinneret, they pass through either a cooling chamber filled with air or a water bath, which solidifies them almost instantly.
Once cooled, the filaments go through a drawing process where they’re stretched between rollers spinning at different speeds. This stretching aligns the molecules inside the fiber, giving each strand its final strength, flexibility, and texture. After drawing, the fibers are cut to length, crimped or texturized to mimic natural hair patterns, and dyed. The finished product gets bundled into the packs you see on store shelves.
Kanekalon, Toyokalon, and Other Fiber Types
Not all synthetic hair is the same. The two most recognized brand-name fibers are Kanekalon and Toyokalon, and they behave quite differently.
- Kanekalon is made by Japan’s Kaneka Corporation and supplied in raw form to factories that cut, texturize, and dye it. It has a relatively low heat resistance (around 80°C or 176°F) and shrinks when exposed to heat, which is actually useful for sealing braids with hot water. It’s flame retardant and widely considered the standard for braiding hair.
- Toyokalon has a higher heat resistance than Kanekalon and a softer feel. It holds curls exceptionally well, making it a popular choice for wigs and curled styles. It tangles less than Kanekalon when worn in loose, uncrimped forms like flowing extensions.
Beyond these two, there are heat-friendly synthetic fibers designed to tolerate styling tools. Standard synthetic hair should generally stay below 177°C (about 350°F), and many products recommend avoiding direct heat altogether, suggesting hot water dipping or rubber bands for styling instead. Heat-friendly versions can handle higher temperatures, though pushing any synthetic fiber to the 260°C (500°F) range that some flat irons reach risks melting and releasing fumes.
Chemical Coatings and Scalp Reactions
Fresh-out-of-the-pack synthetic hair often has a distinctive sheen and slightly stiff feel. That comes from chemical coatings applied during manufacturing to prevent tangling and improve the look of the fibers. These coatings can include alkaline compounds, residual plastics, pesticides, and acrylic-based finishes. For many people, these are the culprit behind the itching, redness, and burning sensation that shows up after installing braids or extensions. This reaction is a form of contact dermatitis, and it’s the coating irritating the scalp rather than the fiber itself.
A common workaround is soaking synthetic hair in a diluted apple cider vinegar bath before installation, which helps strip the alkaline coating. Consumer Reports testing has confirmed the presence of concerning chemicals in several braiding hair products, reinforcing why that pre-treatment step matters.
Environmental Cost of Plastic Hair
Because synthetic hair is plastic, it carries the same environmental baggage as other petroleum-based products. Discarded synthetic hair can take hundreds of years to break down in landfills. As the polymer fibers slowly degrade, they fragment into microplastics that can leach into groundwater and contaminate soil. Toxic additives used to color the fibers, including phthalates, dyes, and flame retardants, can also seep into nearby water sources and harm aquatic life.
Individual fibers shed during wear can break down through sun exposure, potentially contaminating both indoor and outdoor air as well as wastewater systems. Whether these microplastics ever fully mineralize in the environment remains unknown. The improper disposal of synthetic hair, mostly through household waste, means enormous volumes accumulate in landfills each year with no clear path to decomposition.
Researchers are exploring biobased fiber alternatives made from renewable biomass rather than petroleum. These materials use natural feedstocks processed through green extraction methods and modern spinning technologies. While not yet mainstream in the hair industry, biobased fibers are projected to gradually replace traditional petroleum-based options across textile markets as manufacturing scales up.