Nylon, chemically known as polyamide, is the most widely produced synthetic fibre in the world. According to Cambridge Encyclopedia, nylon represents a group of synthetic polymers called thermoplastics. The first nylon polymer was composed of coal, water and air. When nylon is made into rope it is extruded as a continuous filament. Engineering grade polyamide is extruded through the pores of an industrial spinneret to produce fibres. Nylon 6,6 (DuPont patent) is the most common variety of nylon.
Properties of nylon rope include strength, longevity and the ability to absorb shock load. It is flexible, can be stored wet and is resistant to organic solvents, alkalis and acids. It has a high resistance to abrasion. Nylon has good resistance to damaging sunlight UV rays and it resists rot.
Because of its noted strength, nylon rope is often used in heavy load applications. During heavy load, the rope surface remains smooth, allowing it to pass through pulleys and winches without binding. Its resistance to abrasion helps it maintain this smooth surface. Due to these properties, nylon is favoured in rescue operations and fall protection systems where strength, flexibility and smooth operation are critical for saving lives.
Nylon ropes can be purchased in a variety of sizes and types, and nylon can be mixed with other fibres for different characteristics. Some of the different styles of braids include twisted ropes. These ropes are created by twisting several strands of fibre in alternate directions. The different directions of the twisting prevent the rope from unwinding. The twist type rope is also fairly easy to splice into longer lines. This type of rope is generally less expensive since the manufacturing process is fast.
Braid style ropes are smooth with a rounded characteristic form. This style of rope is preferred for uses where the rope is put into conditions of high friction. Braided nylon ropes are used with winches and pulleys. The braided style of rope, because it is manufactured in a slower process where nylon fibres pass in three directions, is more expensive but it provides for a rope that will not twist. This style of braid cannot be spliced.
Different styles of braid create a variety of options. A solid braid rope may have a core that isn't nylon. This complex braiding style is not as strong as other types of ropes but it does have good elongation features. Other braid styles include diamond braids where fibres are woven over and under each other in opposite directions. This is also a strong rope due to its central filler core. Double braided ropes are one rope over the top of another rope. This rope is used in situations where load sharing is important.
When stretched, nylon rope has the ability to remember its original length. This can also be dangerous if the rope breaks. Nylon also loses about 10 per cent of its rope strength when wet. The ends of a nylon rope can be fused with flame or a hot surface to prevent unravelling.