Nylon

A knot, on a rope, made of Nylon Nylon 6,6
Density	1.15 g/cm3
Electrical conductivity (σ)	10−12 S/m
Thermal conductivity	0.25 W/(m·K)
Melting point	463–624 K 190–350 °C 374–663 °F

Nylon stockings, being inspected, in 1954.

Nylon is a type of synthetic fiber. It is one of the most commonly used polyamides, and was first used on February 28, 1935.

Nylon makes a silky material which was first used in toothbrushes. It is strong, hard and water resistant. It is used to make clothes. In fact, polyamides are mostly used for synthetic fibres in clothing. Nylon can also be used to make other materials, such as parachutes, ropes, string for tyres, carpets, fishing nets and cloth and socks.

Nylon was invented by Wallace Carothers at Du-Pont.

Types of nylon

Chemical structures of nylon 6 and nylon 66.

There are many different types of nylon, made from different ingredients in different ways. The two main types of nylon are homopolymer nylon, made from a single chemical, and heteropolymer nylon, made from more than one chemical.

Nylons are numbered based on the number of carbon atoms in their ingredients. A small number usually means a homopolymer, while a larger number or two numbers with a separator (such as a slash or comma) usually means a heteropolymer.

The two most common types of nylon are nylon 6 (a homopolymer made from caprolactam, with 6 carbon) and nylon 66 (a heteropolymer made from adipic acid and hexamethylenediamine, with 6 carbon each). These two molecules are very similar in structure, with the only difference being how the amide groups are arranged: in nylon 6, all C(=O)−N bonds are in the same direction, while they alternate in nylon 66.