Major sectors and their products

Chlor-alkali products Sulphuric acid (sulphur industry) 

Ammonia and fertilizers (nitrogen industry) Phosphoric acid and phosphates (phosphorus industry) 

The petrochemicals sector provides key intermediates, derived from oil and natural gas, such as ethylene, propylene and benzene. These are then used as raw materials for downstream processing in some of the other sectors listed. It is clearly one of the most important sectors of the industry and forms the subject of Chapter 12. 

The polymers sector is the major user of petrochemical intermediates and consumes almost half the total output of organic chemicals which are produced. It covers plastics, synthetic fibres, rubbers, elastomers and adhesives, and it was the tremendous demand for these new materials with their special, and often novel, properties which brought about the explosive growth of the organic chemicals industry between 1950 and 1970. 

Although the dyestuffs sector is much smaller than the previous two, it has strong links with them. This arose because the traditional dyestuffs, which were fine for natural fibres like cotton and wool, were totally unsuitable for the new synthetic fibres like nylon, polyesters and acrylics. A great deal of research and technological effort within the sector has resulted in the amazingly wide range of colours in which modern clothing is now available. 

---