Vinyl is made of polyvinyl chloride (PVC), a plastic polymer built from just two raw ingredients: chlorine and ethylene. Chlorine makes up more than half the weight of the final material, which is unusual for a plastic. The rest comes from ethylene, a compound derived from fossil fuels. What makes vinyl so versatile is that PVC on its own is rigid and almost clear. Everything from soft shower curtains to stiff drain pipes depends on what gets mixed in after the base resin is formed.
The Two Raw Ingredients
Vinyl starts with ethylene and chlorine, both pulled from abundant natural sources. Ethylene comes from natural gas or crude oil through a process called steam cracking, where ethane (a component of natural gas) is superheated with steam to around 950°C. This intense heat breaks apart the ethane molecules and produces ethylene as the primary product, along with hydrogen and methane as byproducts.
Chlorine comes from ordinary salt. In the dominant industrial method, called the membrane cell process, an electric current is passed through dissolved salt (sodium chloride) in water. This splits the salt into chlorine gas, hydrogen gas, and sodium hydroxide. It’s essentially high-powered electrolysis on a massive scale.
These two ingredients are then combined. Ethylene and chlorine react to form a small molecule called vinyl chloride monomer, the single building block that will be chained together into the final plastic.
How Monomers Become Plastic
Vinyl chloride monomer is a gas at room temperature. To turn it into a solid material, manufacturers use a process called free radical polymerization, which is the only method used at industrial scale for PVC production. In this reaction, thousands of vinyl chloride molecules link end to end into long chains, forming the polymer we call polyvinyl chloride.
There are five different commercial variations of this process, but the most common is suspension polymerization. Tiny droplets of vinyl chloride monomer are suspended in water, and a chemical initiator triggers the chain reaction inside each droplet. The result is a fine white powder, the raw PVC resin, ready to be blended with additives depending on its intended use.
What Additives Do to Vinyl
Pure PVC resin is hard, brittle, and nearly transparent. Almost every vinyl product you encounter has been modified with additives that change its flexibility, color, durability, or resistance to heat and UV light. The type and amount of additive is what separates a rigid pipe from a bendy garden hose, even though both start as the same base material.
The most significant category of additive is the plasticizer, a chemical that wedges between PVC chains and allows them to slide past each other, making the material soft and flexible. For decades, a compound called DEHP (a type of phthalate) dominated this role and can make up 20 to 40 percent of the final product’s weight. That’s a massive proportion: in a flexible vinyl medical tube, nearly a third of what you’re holding may be plasticizer rather than PVC itself.
Health concerns about phthalates have pushed manufacturers toward alternatives. Modern non-phthalate plasticizers include compounds based on citric acid esters, adipates (which work especially well at cold temperatures), and a newer option called DINCH developed specifically for sensitive applications like food packaging and medical devices. Each alternative trades off slightly different properties in flexibility, temperature tolerance, and how readily the plasticizer migrates out of the finished product over time.
Vinyl Flooring: Layer by Layer
Luxury vinyl plank flooring is one of the most common places people encounter vinyl in their homes, and it’s far more complex than a single slab of PVC. A typical plank contains six to eight distinct layers stacked together.
The core of the plank is usually one of two composites. WPC (wood polymer composite) is made from wood flour fused with thermoplastic and calcium carbonate, despite the name containing no actual wood planks. SPC (stone polymer composite) is denser, typically around 60 percent limestone (calcium carbonate) mixed with PVC and plasticizers. SPC cores are more rigid and less prone to expansion with temperature changes, which is why they’re popular in kitchens and bathrooms.
Above the core sits a print layer with a photographic image of wood grain, stone, or tile, then a transparent wear layer that protects against scratches and dents. Wear layer thickness is measured in mils (thousandths of an inch). For home use, builders typically recommend at least 12 mil, while commercial spaces often use planks with wear layers up to 28 mil. A UV-protective coating tops the whole stack, and some products add antimicrobial layers or cork and foam backing on the bottom for sound dampening.
What Vinyl Records Are Made Of
Vinyl records are PVC at their core, but the formulation is tuned for a very specific job: holding microscopic grooves that a needle can trace without producing unwanted noise. Without additives, PVC would be too clear and too rough for this purpose.
Carbon black gives records their signature color. It’s not just cosmetic; the pigment also helps stabilize the material. More importantly, records contain compounds described as metal soaps: fatty acid chains held together by metal ions. These act as internal lubricants, creating a surface smooth enough that the stylus glides over it without catching on hard grains or bumps that would produce crackles and pops. Colored vinyl records use alternative pigments in place of carbon black, which is one reason audiophiles sometimes claim black pressings sound cleaner.
Safety in Manufacturing
The finished PVC in your flooring or water pipe is chemically stable, but the vinyl chloride monomer used to make it is a known carcinogen. This matters primarily for workers in manufacturing plants rather than consumers. OSHA limits worker exposure to no more than 1 part per million averaged over an eight-hour shift, with a short-term ceiling of 5 ppm over any 15-minute window. Facilities must begin taking protective action at just 0.5 ppm averaged over a workday.
Once vinyl chloride molecules have polymerized into PVC chains, the monomer is effectively locked into the plastic structure. Residual monomer levels in finished consumer products are trace amounts, regulated separately by agencies overseeing food contact materials and drinking water pipes.