Poly-paraphenylene terephthalamide

Other examples of well-established trade names are Kevlar (poly(paraphenylene terephthalamide)), Plexy-glass (sheets of poly(methyl methacrylate)). Teflon (poly(tetrafluoroethylene)), and Dacron (PET fiber). [Pg.13]

To date, only one class of polymer has been found in which this problem can be overcome and highly successful reinforcement fibres produced. These are the aramld polymers, so-called because they contain both aromatic and amide groups in the molecular chain. Indeed, it is this combination which is the key to their success. Kevlar 49 is currently the most widely used aramid fibre for reinforcement of plastics, and it illustrates the point well. It consists of the polymer poly(paraphenylene terephthalamide) ... [Pg.251]

Aramid Fibers. Aramid (aromatic polyamide) fibers such as Kevlar (DuPont) and Twaron (Akzo Nobel) are made of poly(paraphenylene terephthala-mide). The polymer can be prepared by solution polycondensation of p-phenylene diamine and terephthaloyl chloride at low temperatures. The fiber is spun by extrusion of a solution of the polymer in a suitable solvent (for example, sulphuric acid), followed by stretching and thermal annealing treatment. Tech-nora (Teijin) fibers are slightly different from Kevlar and Twaron as they consist of a copolymer poly(paraphenylene terephthalamide-co-3,4-oxydiphenylene terephthalamide). Various grades of Kevlar fibers are produced (Kevlar-29, 49, and 149), Kevlar-49 being the one more commonly used in composite structures. [Pg.7045]

Kevlar (fibers of Kevlar consist of long molecular chains produced from PPTA (poly-paraphenylene terephthalamide))... [Pg.29]

Figure 77 demonstrates different creep behavior in the narrow deformation intervals for ultimately drawn fiexible-chain and rigid-chain polymers, melt-crystallized and gel-cast UHMWPE films, and poly(paraphenylene terephthalamide) (PPTA) fibers (Kevlar 49, DuPont). Tensile stresses equal to a half of fracture stress CTf were applied. Total deformation to break was equal to 25%, 13%, and 1.32%, respectively, in these samples. To see better a difference in the development of creep process in the investigated polymers, the inserts in Fig. 77 are presented for very narrow deformation intervals. [Pg.196]

A synthetic fiber used in bullet-proof vests, comprised of poly(paraphenylene terephthalamide). [Pg.538]

Major developments in fibre technology have led to ultra-high modulus fibres such as poly-paraphenylene terephthalamide (PPTA) (Kevlar and Twaron) and polyethylene (Dyneema,... [Pg.192]

Aramid pora-Aramid Aromatic polyamide Poly-paraphenylene terephthalamide Aromatic nylon... [Pg.116]

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