The components of PVC originate from the naturally occurring raw materials of petroleum, or natural gas and common salt. The ‘u’ stands for Unplasticised, (sometimes called Unmodified), and it means that the material has not been softened by the addition of chemicals known as plasticisers.
PVC was produced for the first time in 1935 and has been industrially manufactured in large quantities for over 50 years. It has been developed into a material that can offer a wide range of properties and therefore has many different applications. Total PVC production can be split approximately into the following applications:
55% Construction, 16% Packaging, 04% Furniture, 04% Cars, 02% Electrical,19% Others (including Medical and Horticultural.
The process starts with sodium chloride, (common salt) from which chlorine gas is obtained by electrolysis. Petroleum or natural gas is used to produce ethylene, one of many products of the process known as ‘cracking’. Bringing together chlorine and ethylene, liquid vinyl chloride (VC) is produced which is immediately changed in the process by polymerisation to polyvinyl chloride. Although vinyl chloride (VC) itself is toxic, and a closed production process is used, the resultant PVC as a white powder is chemically stable and has no known adverse effects on humans.