PVC - present in virtually all areas of human activity, is a chlorinated hydrocarbon polymer - its basic building blocks are chlorine, carbon and hydrogen. These elements are obtained from sea salt (sodium chloride) and crude oil or natural gas, both of which are mixtures of hydrocarbons. PVC is a thermoplastic. This means that it softens upon heating and hardens upon cooling.

It was first made in 1872. However, the first PVC wasn't very good. When heated or exposed to sunlight, the molecules broke up and an acidic gas was given off. Decades later, scientists discovered that chemicals could be added which would make it stable and resistant to light and heat. This meant good-quality PVC products could be manufactured.

PVC - present in virtually all areas of human activity, is a chlorinated hydrocarbon polymer - its basic building blocks are chlorine, carbon and hydrogen. These elements are obtained from sea salt (sodium chloride) and crude oil or natural gas, both of which are mixtures of hydrocarbons. PVC is a thermoplastic. This means that it softens upon heating and hardens upon cooling.

It was first made in 1872. However, the first PVC wasn't very good. When heated or exposed to sunlight, the molecules broke up and an acidic gas was given off. Decades later, scientists discovered that chemicals could be added which would make it stable and resistant to light and heat. This meant good-quality PVC products could be manufactured.