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Nomex is an example of a meta variant of the aramids (Kevlar is a para aramid). Unlike Kevlar, Nomex strands cannot align during filament polymerization and have less strength: its ultimate tensile strength is 340 MPa (49,000 psi). [2] However, it has excellent thermal, chemical, and radiation resistance for a polymer material.
Aramids are generally prepared by the reaction between an amine group and a carboxylic acid halide group. Simple AB homopolymers have the connectivity −(NH−C 6 H 4 −CO) n −. Well-known aramid polymers such as Kevlar, Twaron, Nomex, New Star, and Teijinconex) are prepared from diamine and diacid (or equivalent) precursors. These polymers ...
Kevlar (para-aramid) [2] is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, [ 3 ] [ 2 ] [ 4 ] the high-strength material was first used commercially in the early 1970s as a replacement for steel in racing tires.
Ignore the substituent R groups – under the assumption the difference between the R groups are negligible: The reaction of two amino acids. Many of these reactions produce long chain proteins. For fully aromatic polyamides or aramids e.g. Kevlar, the more reactive acyl chloride is used as a monomer.
Aromatic polyamides (e.g. Kevlar and Nomex) are made by polycondensation in N-methyl-pyrrolidone and calcium chloride solution. This process is one of two used in the production of sodium polyacrylate, a superabsorbent polymer used in disposable diapers.
Military webbing, or web gear otherwise known as Mil-Spec webbing, is typically made of strips of woven narrow fabrics of high tensile strength, such as nylon, Kevlar, and Nomex. When these materials are used for parachute and ballooning applications, they must also conform to PIA (Parachute Industry Association) standards. [8]
aromatic polyamids (aramids) such as Twaron, Kevlar and Nomex thermally degrade at high temperatures and do not melt. These fibers have strong bonding between polymer chains; polyethylene (PE), eventually with extremely long chains / HMPE (e.g. Dyneema or Spectra).
Zylon body armor panels sometimes cost twice as much as Kevlar or 35% more than other advanced materials. [9] Despite "sticker shock", the marketing for Zylon body armor described incredibly low weight and thickness, but shockingly high protection, causing some to refer to it as a "miracle fiber".