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Rope Materials in Chronological Order
History: Cotton is included here for completeness. Not as strong as hemp, it is a poor substitute when strength is required.
However, cotton is soft and can be bleached white. It makes very attractive decorative rope for purposes such as handrails, drapery pulls, and bell ropes.
History: Before the advent of synthetic fibers, industrial, marine, and climbing ropes were made of hemp that, for durability, was soaked in pine tar. The fiber comes from Cannabis sativa, a variety that, in marked contrast to Cannabis indica, yields only minute amounts of any psychoactive drug. Hemp fiber is one of the longest and strongest of the natural fibers. In his "History of Rope" Bill Fronzaglia writes "...it was known that Hemp retains more strength when the yarn is twisted to the right. This resulted in a left hand strand, and a right hand rope. It wasn't until modern times that microscopic examination of the plant illustrated that the structure of the plant has a natural twist that causes this effect." This explains why Left Hand Strands twisted together as Right Hand lay ("Z" twist) make stronger hemp rope. Unfortunately, Fronzaglia provides no link to this interesting piece of research.
Nylon®, Perlon® (Polyamide):
History: The Polyamide 6,6 (Nylon® – by Dupont) and Polyamide 6 (Perlon® – IG Farben) were developed in the late 1930's. Nylon® was first introduced in 1939 in the form of stockings. They were an overwhelming success. Almost immediately, however, the requirements of World War II consumed the available supply and Nylon® stockings vanished until 1946. The name Nylon® embraces a number of related compounds. The variants usually used for manufacturing rope are Nylon 6 and Nylon 6,6. Their properties are almost indistinguishable except for a small difference in melting temperature.
Dacron®, Terylene® (Polyester):
History: The Polyester, Terylene®, was developed by Imperial Chemical Industries in 1941. The rights were purchased by duPont in 1946 who subsequently developed the related similar fiber, Dacron®. The introduction of Dacron® rope in 1953 changed things again. The practical benefits of Nylon® were retained with the critical difference that elasticity was markedly reduced. In 1957 Samson introduced the Double Braid construction, and Dacron® ropes were rapidly adopted for halyards, sheets, and static climbing ropes.
A chemical group which includes both polypropylene and polyethylene. When describing rope, polyolefin may refer to a mixture or to either one of these fibers.
History: Polypropylene was first synthesized in 1954 and produced commercially from 1957 onwards.
History: Polyethylene was first synthesized in 1933 and produced commercially from 1939 onwards.
The fiber used in rope is similar to Polypropylene but slicker with better abrasion resistance and a lower melting point. It also floats and is most commonly found in small diameters. e.g., as a water-ski towline. It is used to make nets and is widely used in the fishing industry.
First described in 1968, carbon fiber exhibits very high tensile strengths – but has not proved suitable to make rope: the high theoretical strength is lost during manufacture into rope and braiding has not proved satisfactory. It has been used as a high-tech sail fabric, to reinforce concrete, and in support stays for cranes and towers but not for the crane's running cables.
Kevlar®, Twaron®, and Technora® (Aramid):
High Modulus Polyamide was introduced as Kevlar® (1973), Twaron® (1978), and Technora® (1976). These heat resistant fibers have long chain molecules highly oriented in the axis of the fiber. They are best known for their use in body armor fabric.
Spectra®, and Dyneema® (HMPE):
Introduced as Spectra® (1975) and Dyneema® (1979), the HMPE (High Modulus Polyethylene) fibers are composed of exceedingly long molecules with a molecular weight in the 2 to 6 million range.
The fibers are tough (excellent abrasion resistance) and slippery (very low coefficient of friction), but kinking or compression damages them relatively easily.
This High Modulus Polyester, LCAP (Liquid Crystal Aromatic Polyester), was introduced as Vectran® (1990). Vectran® is somewhat similar to the Aramid ropes but has a high melting point.
Vectran® exhibits no creep even at high temperatures loaded to 50% of its breaking strain. It tolerates kinks, bends, and knots better than the HMPE ropes and exhibits good knot holding properties.
PBO (Poly-p-phenylenebenzobisoxazole) was introduced as Zylon® in the 1980s. It is expensive and degraded by light - even artificial light. So, it requires a sheath, e.g., polyester.
Disclaimer: Any activity that involves ropes is potentially hazardous. Lives may be at risk - possibly your own. Considerable attention and effort have been made to ensure that these descriptions are accurate. However, many critical factors cannot be controlled, including: the choice of materials; the age, size, and condition of ropes; and the accuracy with which these descriptions have been followed. No responsibility is accepted for incidents arising from the use of this material.