Reinforced plastics Aramid fiber

AFRP aramid fiber reinforced plastic AOZ antiozonant... 

Based on contents of an RP other terms are used to identify an RP. Examples include glass fiber reinforced plastic (GFRP), aramid fiber reinforced plastic (AFRP), carbon fiber reinforced plastic (CFRP), graphite fiber reinforced plastic (GFRP), boron fiber reinforced plastic (BFRP), etc. 

Odagiri, T., K. Matsumoto and H. Nakai (1997). Fatigue and relaxation characteristics of continuous aramid fiber reinforced plastic rods. Non-Metallic (FRP) Reinforcement for Concrete Structures, FRPRCS-3, Sapporo, Japan, pp. 227-234. 

In the USA, initial work in repairing bridge columns used glass and aramid fiber reinforced plastic, and buildings were repaired with bonded steel plates, but it is now believed that these will be replaced by cfrp. 

Densely cross-linked PCN networks, synthesized by polymerization, via cy-clotrimerization reaction, of dicyanic ester of bisphenol A [159-161], consist of rigid triazine heterocycles as junctions connected with bisphenol A remainders (see a scheme in Fig. 26). At the total conversion of cyanate groups (Xcn pcn 1). PCN exhibits high Tg 300°C and rigidity, good adhesion to different substrates and chemical resistance, as well as low values of dielectric constant and water uptake. This allowed in particular its application as the matrix for glass- and aramid fiber-reinforced plastics in the electronics and aerospace industries. 

Creep tendency in glass and carbon fibers is very low, in aramid fibers it is higher. In combination with organic matrices or adhesives, their viscoelastic behavior determines creep tendency in the composite. In comparative relaxation tests up to 1000 h at approx. 50% short-term strength, carbon fiber reinforced plastics indicated virtually no creep, glass fiber reinforced plastics exhibited low creep (approximately twice as much as pre-tensioned steel, while aramid fiber reinforced plastics showed four to five times as much creep [1011]. 

Creep behavior of aramid fiber reinforced plastic rods in air and alkaline solution, with and without embedding in concrete [lOIIJ... 

GFRP Glass fiber reinforced plastic CFRP Caibon reinforced plastic ARFP Aramid fiber reinforced plastic. 

High-pressure water can also be used to water jet cut many plastic materials. A fine jet of water (either plain or with abrasives added) is directed at the part at pressures of 60,000 psi from a fine nozzle. Automated robotic equipment is available to water jet cut intricate patterns. This method is very attractive for many hard-to-cut materials such as aramid fiber-reinforced composites. The water jet cuts most materials quickly without a burr and does not introduce stresses in the material. 

Yeaple, F. Aramid Fibers Reinforce Lightweight Plastic Sails. Design News, p. 128, Nov. 

Water-saturated rods made from aramid or glass fiber reinforced plastics exhibit a reduction of 8 to 10% in short-term strength compared to dry rods (which is largely reversible). At elevated temperatures, permanent hydrolytic damage may occur [1011]. Therefore, short-term tests are often performed applying loads far above actual operating loads and under time-dependent physico-chemical ambient conditions that in service may cause very different softening effects at much lower mechanical loads. 

The use of traditional composites made by glass, aramid, or carbon fiber-reinforced plastics has recently been discussed critically because of increasing environmental consciousness [8]. Thus, the recent research and development (R D) efforts have led to new products based on natural resources. Some of these are biodegradable polymers like PLA, cellulose esters, polyhydroxyalkan-otes (PHAs), and starch polymers. Furthermore, natural fiber-reinforced plastics made of natural fibers like flax, hemp, kenaf, jute, and cotton fibers are important R D achievements. Composites made of natural fibers and biopolymers... 

Because people everywhere tend to take their fun seriously, they spend freely on sports and recreational activities. The broad range of properties available from plastics has made them part of all types of sports and recreational equipment for land, water, and airborne activities. Roller-skate wheels are now abrasion- and wear-resistant polyurethane, tennis rackets are molded from specially reinforced plastics (using glass, aramid, graphite, or other fibers), skis are laminated with plastics, and so on. 

By this time the industry required a more inclusive term to describe RPs, so composite was added. Thus the name in the plastics industry became Reinforced Plastic Composites. More recently they became known only as Composites. However composites identify many other combinations of basic materials (Table 6-18). The fiber reinforcements included higher modulus glasses, carbon, graphite, boron, aramid (strongest fiber in the world, five times as strong as steel on an equal-weight basis), whiskers, and others (Table 6-20 and Figs. 6-13 and 6-14). In... 

A third interesting aspect of this story is that Du Pont s aramide fiber was not specifically the result of market-driven research. When this fiber was patented in 1971 there was no commercial application in view. However, within ten years, three varieties of Kevlar fiber were commercialized by Du Pont for dozens of reinforced plastic applications in radial passenger tires, belts, in protective clothing, such as gloves or ballistic and flak vests, in ropes and cables in racing kayaks and canoes, and in commercial aircraft. Thus the Kevlar fiber by no means resulted from the functional, bottom-up, approach which is sometimes considered as a major characteristic of materials science. The aramide fiber resulted from the traditional style of industrial research which was successful in the plastic era and confirms the leadership of chemistry in materials technologies. 

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