Page 50 - Curriculum Visions Dynamic Book

(Above and right) This photograph shows Kevlar fibres embedded in the material at the back of the wing of a microlight. This part of the wing experiences the greatest forces and so has the risk of tearing in severe weather conditions.
An American research chemist, Stephanie Kwoleck, discovered a solvent that could make Kevlar aramid fibre. Kevlar threads are stronger than steel, yet very light and are used in many applications where these properties are useful, such as in aircraft, spacecraft, and bulletproof vests.
Nylon 6 is made from building blocks having six carbons in the chain, but with an amine at one end and an acid at the other. Thus only one form of monomer is needed to conduct the reaction.
Nylon 6,6 – another very common fibre polymer – is made by reacting molecules of adipic acid (containing six carbons in a chain) with the amine hexamethylenediamine (also six carbon atoms). A representation of this reaction is shown on page 14. In another variant a diamine containing ten carbon atoms is used, and so on.
As with the polyesters, nylons have regular structures, and that allows good interchain forces that give the nylon its high strength.
(Right) Space suits contain multiple layers of nylon fabrics.
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