What is uPVC exactly?
uPVC is known as rigid vinyl in America. uPVC stands for unplasticised Polyvinyl Chloride. Polyvinyl chloride (PVC) is a compound of chlorine, carbon and hydrogen. These are three abundant elements found in nature.
The chlorine is taken from salt (sodium chloride) and the carbon and hydrogen is taken from either petroleum or natural gas. Thus, although uPVC looks like an artificial material, it comes from very simple components. Whereas, there are fears of dwindling supplies of petroleum and natural gas in the world, few people worry about the amount of salt left in nature. After all, salt can easily be extracted from sea water.
PVC was first made in 1935 and has been manufactured in large amounts ever since. PVC and uPVC was quickly found to have a range of properties and thus was suitable for many different purposes. Presently, PVC use can be categorized as follows:
- 55% used in the construction industry
- 16% for packaging
- 4% for furniture making
- 4% in the production of cars
- 2% in electrical applications
The remaining 19% is used in a variety of ways including for horticulture and for medicine.
How PVC is made?
First sodium chloride is taken (salt). From this, chlorine is extracted via electrolysis. In a separate process petrol or natural gas is broken down to produce ethylene. This process is often called ‘cracking’. Next the chlorine and ethylene are combined to make liquid vinyl chloride (VC). After this, the vinyl chloride is altered by polymerization into polyvinyl chloride or PVC. Because vinyl chloride is toxic the final process is done in a closed production process. The resulting PVC is a stable white powder.
The PVC is often plasticized to make it soft. This produces the PVC that is used for clothing, furniture covers etc. If the PVC is not plasticized it can be made into a hard and rigid material called uPVC that is ideal for window applications, conservatories, doors etc.
Benefits of uPVC
uPVC was found to be ideal for the construction industry because it did not react with air or water and thus did not rot, expand etc. under weathering. It is cheap to make. It is hard and can withstand hard impacts.
Another benefit of uPVC is that it is light and easy to work with. uPVC can be heated and molded into shape. This has meant that it is possible to recycle uPVC. Once it is separated from glass, steel, aluminum etc. uPVC can be melted down and reused.
Finally uPVC is ideal for double glazing and other insulation and widow treatments in a building.
uPVC and the environment
uPVC has proved indispensible in so many ways. Its production, disposal and recycling must be carefully regulated to insure it is a material that falls in line with the very latest in environmentally conscious thinking.