Aramid - Knowledge - Baolilong New Materials

Aramid fibers are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated body armor fabric and ballistic composites, in marine cordage, marine hull reinforcement, and as an asbestos substitute. The name is a blend of "aromatic polyamide".

The chain molecules in the fibers are highly oriented along the fiber axis. As a result, a higher proportion of the chemical bond contributes more to fiber strength than in many other synthetic fibers. Aramides have a very high melting point (>500 °C).

Common aramid brand names include Kevlar, Nomex, and Twaron.

Kevlar is a heat-resistant and strong synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965,this high-strength material was first used commercially in the early 1970s as a replacement for steel in racing tires. Typically it is spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components.

Kevlar has many applications, ranging from bicycle tires and racing sails to bulletproof vests, because of its high tensile strength-to-weight ratio; by this measure it is five times stronger than steel.[2] It also is used to make modern marching drumheads that withstand high impact. It is used for mooring lines and other underwater applications.

Nomex is a flame-resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967.

Twaron (a brand name of Teijin Aramid) is a para-aramid. It is a heat-resistant and strong synthetic fibre developed in the early 1970s by the Dutch company Akzo Nobel's division Enka BV, later Akzo Industrial Fibers. The research name of the para-aramid fibre was originally Fiber X, but it was soon called Arenka. Although the Dutch para-aramid fiber was developed only a little later than DuPont's Kevlar, introduction of Twaron as a commercial product came much later than Kevlar due to financial problems at the AKZO company in the 1970s.

Aramid fibers share some general characteristics that distinguish them from other synthetic fibers:

High strength

Good resistance to abrasion

Good resistance to organic solvents

Non-conductive

No melting point

Low flammability

Good fabric integrity at elevated temperatures

These unique characteristics derive from the combination of having stiff polymer molecules with a strong crystal orientation as well as close interaction between the polymer chains due to the hydrogen bonds.

Uses

flame-resistant clothing

heat-protective clothing and helmets

body armor,[10] competing with PE-based fiber products such as Dyneema and Spectra

composite materials

asbestos replacement (e.g. brake linings)

hot air filtration fabrics

tires, newly as Sulfron (sulfur-modified Twaron)

mechanical rubber goods reinforcement

ropes and cables

V-belts (automotive, machinery, equipment, and more)[11]

wicks for fire dancing