Polyvinyl chloride

This is a type of plastic.

It is made in a very large way. Millions of tons are made each year.

This plastic can be hard or soft. Hard plastic makes pipes and windows. It also makes cards for banks.

We can make it soft by adding things. This helps make items like boots. It also helps make soft toys.

People use this plastic in many ways. It can be used for floor tiles. It can even be used for wires.

This plastic is all around us. Can you find it in your home?

Polyvinyl chloride is a type of plastic. Many people call it PVC.

It is the third most common plastic made in the world. About 40 million tons are made each year.

PVC can be hard or soft. Hard PVC is used to build things. It makes pipes, doors, and windows. It also makes cards for banks.

We can make PVC soft by adding plasticizers. These are special parts that make the plastic bend.

Soft PVC is used for things like boots and clothing. It is also used for inflatable toys.

Making PVC is a big job. It starts with a tiny part called a monomer. Workers put these parts in a large tank with water. They use a set of steps called polymerization to link the parts together. This makes long, strong chains.

PVC is very useful. It can protect wires from fire. It also keeps water moving through pipes. It is a big part of our modern world.

Polyvinyl chloride is a very common type of plastic. Many people call it PVC for short. It is the third most widely produced synthetic polymer in the world.

Every year, about 40 million tons of PVC are made. This material can be very hard or very soft. Rigid PVC is used for building things like pipes, doors, and windows. It is also used to make plastic bottles and membership cards. You might even see it used in window frames or siding on a house.

To make PVC, scientists use a process called polymerization. This means they link tiny parts together to make long chains. These tiny parts are called vinyl chloride monomers.

Most of the time, workers use a method called suspension polymerization. They put the monomers and water into a large reactor. They also add a special starter called an initiator. The mixture is kept under pressure and mixed constantly. This helps the particles grow to a uniform size. The reaction creates heat, so the machine must be cooled down.

People have been studying this plastic for a long time. A German chemist named Eugen Baumann first made it in 1872. He found a white solid inside a flask of vinyl chloride. This flask had sat on a shelf for four weeks without sunlight. Later, in the early 1900s, two other scientists tried to use it for products. Ivan Ostromislensky and Fritz Klatte both had a hard job. The plastic was too rigid and brittle to work well back then. In 1926, Waldo Semon found a way to fix this. He blended the plastic with additives to make it flexible.

PVC can be changed by adding different ingredients. These ingredients are called additives. Plasticizers are a special type of additive that makes the plastic soft.

Without these, PVC stays a hard, white, brittle solid. Flexible PVC can have over 85% plasticizer by its mass. This makes it perfect for making soft boots, clothing, or inflatable toys. Other additives like heat stabilizers help the plastic stay strong when it gets warm. Some additives even help the plastic resist fire. This is why PVC is used to cover electrical cables.

You can find PVC in many places in your daily life. It is used to make many things you might recognize. For example, it is used to make vinyl records for music.

It is also used to make the clear tubing used in hospitals. Even the pipes under your house might be made of PVC. This is because it is good at resisting chemicals and is not very expensive. China produces about half of the world's PVC. The largest single company making it is Shin-Etsu Chemical in Japan.

Polyvinyl chloride, often called PVC or vinyl, is a synthetic polymer of plastic. It is the third most widely produced synthetic polymer on Earth. Every year, the world produces about 40 million tons of this material. PVC is a white, brittle solid in its pure form. However, it is very versatile because its physical properties can be changed. This makes it useful for everything from hard construction materials to very soft clothing.

Scientists create PVC through a chemical process called polymerization. This process links small units called vinyl chloride monomers (VCM) into long, strong chains. About 80% of all production uses suspension polymerization. In this method, VCM and water are placed into a reactor with an initiator. The initiator is a substance that starts the chemical reaction. The vessel is pressurized and mixed constantly to keep the particles a uniform size. This reaction is exothermic, which means it generates its own heat. Because of this, the reactor must be cooled to manage the temperature.

There are different ways to perform this polymerization. Suspension polymerization creates particles with diameters between 100 and 180 micrometers. Emulsion polymerization is another method used for about 12% of production. This method creates much smaller particles, averaging around 0.2 micrometers. Bulk polymerization accounts for the remaining 8% of production. The resulting polymer is linear and very strong. About 57% of the mass of PVC is made of chlorine. This high chlorine content gives PVC different properties than other plastics like polyethylene.

Raw PVC is unmodified and requires additives to become useful. These additives are called compounds. Different end products require different ingredients to meet specific needs. Heat stabilizers are essential because raw PVC has poor heat stability. Without them, the material can lose hydrogen chloride (HCl) at temperatures above 70 degrees Celsius. This loss is autocatalytic, meaning the process helps itself continue. Other additives include UV stabilizers, flame retardants, and pigments. These ingredients ensure a window frame lasts a long time or a cable resists burning.

One of the most important additives is the plasticizer. Plasticizers change PVC from a rigid solid into a soft gel. PVC is unique because it can accept very large amounts of these substances. Flexible PVC can contain over 85% plasticizer by mass. The most common plasticizers are phthalates, which are diesters of phthalic acid. Scientists categorize them as high or low molecular weight. Low-molecular-weight phthalates, like DEHP, are being phased out due to health risks. Higher-molecular-weight versions, such as DINP, are generally considered safer alternatives.

The history of PVC involves several important discoveries. German chemist Eugen Baumann first synthesized PVC in 1872. He discovered the white solid after a flask of vinyl chloride sat on a shelf for four weeks. In the early 20th century, Ivan Ostromislensky and Fritz Klatte tried to use it commercially. They struggled because the polymer was too rigid and brittle to process easily. In 1926, Waldo Semon and the B.F. Goodrich Company solved this problem. They developed a method to plasticize PVC by blending it with additives. This discovery allowed PVC to be used in many new ways.

Today, PVC is used in many massive industries. About half of the world's PVC production capacity is located in China. The largest single producer is Shin-Etsu Chemical in Japan, which holds a 30% global share. In construction, PVC is vital for pipes, doors, and windows. In the United States, PVC accounts for 66% of the household market for pipes. It is also used for electrical cable insulation because it is a good insulator. In a fire, the chlorine in PVC helps scavenge free radicals, which makes the coating fire-retardant.

From music to medicine, PVC is everywhere. It is used to make phonograph records, also known as vinyl records. In hospitals, it is used for intravenous tubing and blood bags. Specifically, the combination of PVC and the plasticizer DEHP was used for blood bags because it stabilizes red blood cells. This helps prevent hemolysis, which is the rupture of red blood cells. We also see PVC in everyday items like flooring, signage, and inflatable products.