| Contents for this page | Related topics |  |
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Condensation polymers Nylon Other condensation polymers Additional questions |
The petroleum industry The chloralkali and Solvay processes The polymer industry (1) The fertiliser industry Ammonia - Nitric acid - Sulphuric acid Electrochemical cells |
 Data Glossary |
| Learning Outcomes | ||
| After studying this section, you will be familiar with (a) the chemical principles underlying the manufacture of nylon and (b) the composition of some other commonly-used condensation polymers. | ||
CONDENSATION POLYMERS are polymers prepared by the condensation of two types of molecules, ultimately linking these molecules with strong covalent bonds:
A great variety of such polymers are a fact of everyday life, as they are widely used in the home, in industry and for sports activities.
Nylon, discovered shortly before the second world war, is a polymer prepared solely from coal, air and water. This material first came into prominence as a replacement for womens' silk stockings, and during the war, due to a shortage of natural silk from Asia, it was found that it was an ideal replacment for the silk used in parachutes. Nylon is a POLYAMIDE polymer, containing the C-CO-NH-C AMIDE functional group. One common type is the so-called nylon-66, so named becaused the two monomers used, adipic acid and hexamethylene diamine (HMDA) both contain six carbon atoms.
Nylon is a thermoplastic polymer, and can be spun, cast, machined and moulded, and thus finds a wide variety of uses, such as nylon fabrics, clothing and footwear, machine parts, fishing line, ropes, guitar strings, and all sorts of sporting equipment.
Various types of condensation polymers exist and are manufactured on a huge scale. The major ones are mentioned below:
These are thermoplastic polymers that contain the ester group (C-CO-O-C). Polyethylene terephthalate (PET), (whose partial structure is shown above) is widely used, as it can be spun into threads and woven into cloth. As such, it finds ready use in the clothing industry. Other major uses are in the manufacture of plastic bottles, films, and as high-gloss varnishes.
These are a sub-group of thermoplastic polyesters, containing the carbonate group C-O-CO-O-C. Some of these are very durable, impact-resistant, and more transparent than glass, and so find use as lenses for spectacles and sunglasses. Other uses are for CDs and DVDs, lenses for motor car lights, glazing, and the manufacture of numerous small plastic items, including bottles for household and laboratory use
This remarkable material is a polyamide polymer, with the amide group C-CO-NH-C. It is said to be 5 times stronger than steel on a weight basis. It is used as reinforcement for boat hulls, airplanes and bicycles, as well as for the manufacture of body armour ("bullet-proof vests") for the military and the security industry.
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