There are a number of different materials used in the manufacture of ropes. This page details some of the most popular.
ARAMIDS
One of the first high performance materials to be used in the rope industry were aramids such as Kevlar, Technora and Twaron. Aramid or poly-(para-phenylene terephthalamide) is a low stretch, high strength fibre with good resistance to creep and high temperatures. However its UV and abrasion resistance are poor, this means that an aramid rope is best jacketed in another material such as polyester. Aramids have a poor resistance to knots and bending requiring large sheaves on pulleys.
Within the aramid family there are also Meta-Aramids (poly-(meta-phenylene isophthalamide)) such as Nomex and Tejinconex, these are meta linked aramids and have excellent resistance to flames and heat but are not as strong as para linked aramids.
HMPE
The next “exotic” material to hit the market was High Modulus Polyethylene e.g. Dyneema and Spectra. Like aramids this is a low stretch high strength fibre, however HMPE ropes are lighter than aramids (relative density of HMPE 0.97) and do not suffer from the same degree of strength loss when used around small D:d ratios. Read our pages on Dyneema to learn more
VECTRAN
Vectran or Aromatic Liquid Crystal Polyester is yet another high strength low stretch material. Vectran has very low creep and a higher tenacity than Aramid and is also very resistant to heat.
PBO
PBO or poly (p-phenylene-2, 6-benzobisoxazole) is marketed under the trade name Zylon. This material is relatively new to the market. PBO is one of the strongest materials currently available for rope making; it has very low stretch and exceptional resistance to high temperatures. However, like aramids this fibre needs to be protected from UV and abrasion.
POLYESTER
This synthetic material has an excellent resistance to UV and abrasion, polyester is unaffected by water. This combination of properties means that polyester is the material used in protective cover braids as well as in pure polyester ropes. Polyester has a density of 1.38, melting point of 260 deg C and an extension to break of about 12%.
NYLON
Also known as Polyamide, this material when dry is slightly stronger than Polyester but will be weakened by up to 10% when it gets wet. Nylon has good UV and abrasion resistance. The primary advantage of nylon over other materials is its 30% stretch to break, this makes nylon ideal in applications where energy absorption is a requirement. Nylon has a relative density of 1.14 and a melting point of 220 deg C.
POLYPROPYLENE
Polypropylene is a very light material with a density of 0.91, this means a rope in this material will float. Polypropylene has a moderate resistance to UV and abrasion. The extension to break is similar to polyester but the strength is not as high. Polypropylene has a relatively low melting point at 170 deg C. Polypropylene has a good resistance to a huge range of chemicals.
POLYETHYLENE
This material has similar properties to Polypropylene but with a slightly better UV resistance. The relative density is 0.97 and the melting point is about 165 deg C.
PEEK
PEEK (polyetheretherketone) is a member of the Polyketone family of polymers that offer exceptional thermal and dimensional stability. The real value of Zyex PEEK fibres is in their giving longer life at the extremes of temperature, steam or chemical exposure in a wide variety of abrasive conditions.
