I can find many things which around my life are made from nylon, like clothes, silk stockings, carpet and etc. Nylon is one kind of condensation polymer. Its composing unit is connected by dicarboxylic acid, therefore sometimes it is also called polyamide. Raw materials of nylon are coal, water and air.
Characteristics of nylon:
★Variation of luster: nylon has the ability to be very lustrous, semilustrous or dull.
★Durability: its high tenacity fibers are used for seatbelts, tire cords, ballistic cloth and other uses.
★High elongation
★Excellent abrasion resistance
★Highly resilient (nylon fabrics are heat-set)
★Paved the way for easy-care garments
★High resistance to:
o Insects, fungi and animals
o Molds, mildew, rot
o Many chemicals
★Used in carpets and nylon stockings
★Melts instead of burning
★Used in many military applications
★Good specific strength
The most common nylon is Nylon 6, 6 which refers to the fact that the diamine (hexamethylene diamine) and the diacid (adipic acid) each donate 6 carbons to the polymer chain. Its reaction is:
| Typical Physical Characteristics of Nylon 66 | ||
| Property | Unit | Value |
| Specific gravity | | 1.14 |
| Density | kg/m3 (lb/ft3) | 1140(71.17) |
| Melt density | kg/m3 (lb/ft3) | 965(60.24) |
| Bulk density | kg/m3 (lb/ft3) | Ca. 670(41.83) |
| Water absorption(24h) | % % | 1.3 1.2 |
| Melting point | °C (°F) | 260(500) |
| Glass transition temperature | °C (°F) °C (°F) | 100(212) 90(194) |
| Self-ignition temperature | °C (°F) | >420(788) |
| Flash ignition temperature | °C (°F) | >400(752) |
| Specific heat | J/g·K (ft·lbf/lb·°F) | 1.7 (3.16 ´ 10–4) |
| Thermal conductivity | W/m·K(Btu/ft·h·°F) | 0.3 (0.17) |
An earlier nylon was made from pentamethylene diamine and sebacic acid. Pentamethylene diamine has five carbon atoms and sebacic acid has ten carbon atoms. So the nylon they make is called nylon 5-10, or polyamide 5-10.
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