Polychloroprene is a synthetic rubber made by polymerizing a chemical called chloroprene (2-chloro-1,3-butadiene). You probably know it better by its original brand name, Neoprene, which has become the common term for this material in everyday life. It was one of the first commercially successful synthetic rubbers, and today it shows up in everything from wetsuits and laptop sleeves to industrial conveyor belts and construction adhesives.
How Polychloroprene Is Made
The production process starts with chloroprene monomer, a liquid chemical derived from butadiene. Manufacturers mix this monomer with other ingredients and an aqueous caustic solution to create an emulsion, essentially a stable mixture of tiny droplets suspended in water. Free radicals then kick off the polymerization reaction, linking chloroprene molecules into long polymer chains. When the chains reach the desired length, chemical scavengers stop the reaction.
At that point, any unreacted monomer is removed. The resulting polychloroprene can be sold in two forms: as a latex (a milky liquid colloid used directly in coatings and dipped goods) or dried into solid sheets and chips for molding and extrusion. The entire process takes place in enclosed buildings because chloroprene gas poses occupational exposure risks for workers.
Key Physical Properties
Polychloroprene stands out among synthetic rubbers for its unusual combination of traits. It maintains flexibility across a wide temperature window, typically from -50°C to 120°C (-58°F to 248°F). That range makes it useful in both freezing outdoor environments and hot engine compartments.
Its other notable properties include:
- Weather and ozone resistance: Unlike many rubbers that crack and degrade when exposed to sunlight, ozone, and moisture, polychloroprene holds up well outdoors over long periods.
- Flame resistance: It self-extinguishes rather than continuing to burn, which is rare for a rubber. This makes it valuable in electrical and mining applications where fire safety matters.
- Moderate oil resistance: It tolerates contact with oils and greases reasonably well, though it isn’t the best choice for prolonged immersion in fuels.
- Good mechanical strength: It resists tearing and abrasion, giving it a long service life in demanding industrial settings.
Where You’ll Find It
Polychloroprene’s versatility means it appears in a surprisingly wide range of products. In consumer goods, the most recognizable use is probably wetsuits and diving suits, where its flexibility, water resistance, and insulating properties are ideal. It’s also the material in many laptop sleeves, phone cases, and orthopedic braces sold under the “neoprene” label.
Industrially, the applications are far more varied. A large volume goes into adhesives: contact cements, construction mastics, foil laminating adhesives, and general-purpose glues that bond rubber, wood, metal, and fabric. If you’ve ever used a yellow contact cement from a hardware store, it was likely polychloroprene-based.
Beyond adhesives, polychloroprene is the dominant rubber in heavy-duty conveyor belts for mining, V-belts for machinery, and cable jackets in transport, welding, and mining equipment where flame retardancy is critical. It lines hoses, seals gaskets, dampens vibrations in automotive mounts, and forms the coated fabrics used in inflatable structures and airbags. It even serves as membrane diaphragms in valves at nuclear power plants in Sweden.
Polychloroprene vs. Nitrile Rubber
Nitrile rubber is the other common synthetic rubber people encounter, especially in disposable gloves. The two materials fill different roles. Nitrile excels at resisting oils and fuels, making it the go-to choice for automotive seals and fuel-handling equipment. Polychloroprene, on the other hand, is the better pick for anything exposed to weather, UV light, or heat. It handles temperatures up to about 120°C (248°F), compared to nitrile’s ceiling of around 100°C (212°F), and its flame resistance is substantially better.
Neither material is dramatically superior for chemical resistance in general. The choice usually comes down to whether the application involves oil exposure (favor nitrile) or outdoor weathering and heat (favor polychloroprene).
Use in Medical Gloves
Polychloroprene has carved out a small but important niche in healthcare as an alternative to natural rubber latex gloves. Natural latex triggers allergic reactions in a meaningful number of healthcare workers and patients, ranging from skin irritation to serious anaphylaxis. Polychloroprene gloves eliminate that specific protein-based allergy risk because they contain no natural rubber proteins.
That said, polychloroprene currently holds only about 2% of the surgical glove market. One reason is cost: synthetic surgical gloves are more expensive than latex. Another consideration is that some of the chemical accelerators used to manufacture polychloroprene gloves overlap with those used in natural latex production, so workers with chemical sensitivities (as opposed to latex protein allergies) may not see full relief from switching.
A Brief Origin Story
Polychloroprene was developed in the early 1930s by Wallace Carothers, a theoretical organic chemist who left Harvard to lead DuPont’s fundamental research program. Carothers’ group at DuPont produced two landmark materials: neoprene (polychloroprene) and nylon. Both discoveries transformed industrial manufacturing and helped establish the model of corporate-funded basic science research that became standard in the 20th century. DuPont trademarked the name “Neoprene,” which became so widely used that most people still call the material by that brand name rather than its chemical name.
Recycling and Environmental Challenges
Like most synthetic rubbers, polychloroprene is not biodegradable in any practical timeframe. Once it reaches the end of its service life, it typically goes to landfill. In some demanding applications, such as the inner linings of slurry-transport hoses, up to 40% of the material erodes away during use, with the remaining 60% discarded as waste after replacement.
Recycling polychloroprene is technically possible but difficult. The chemical crosslinks that give the rubber its strength and elasticity also make it resistant to being reformed. Researchers have demonstrated methods for grinding cured polychloroprene into granules and re-molding them under heat and pressure, but the recycled material only partially recovers its original tensile strength. Newer experimental approaches involve designing crosslinking systems that can be reversed at high temperatures, allowing the rubber to be reshaped and reused. These methods are still in early stages, and no large-scale recycling infrastructure for polychloroprene exists yet.