Engineered fiber-reinforced molding

Fiber reinforcement of polymers allows us to use them in engineering applications that were previously off limits, We use fiber reinforced injection moldings in many under-the-hood automotive applications, such as rocker box covers and front end modules, which support the radiator, cooling fan, and hood latch, that are subjected to a wide range of temperatures. 

The Bell/Boeing V22 Osprey tilt-rotor aircraft uses carbon fiber-reinforced polyether etherketone (PEEK) for doors and housings of the engine air particle separator and for fuel vent tanks (Figure 6.44). TP polyimide (TPI) forms the basis for an injection-molded spline adapter in the drive train which tilts the rotors. Costs were reduced some 22%. The parts were developed by RTP Company with Bell Helicopter and molder RAM Inc., Texas. The tanks are molded by the lost core process. 

MAJOR APPLICATIONS Blow molded bottles. Extruded film and sheets for food packaging, including blend, multilayer, and laminate with nylon 6, PET, and polyolefins. Monofilament for bristle and filter cloth. Glass fiber reinforced injection molding materials used to make parts for the automotive, machine, electrical/electronic, civil engineering, sports, and other industries as a metal substitute. 

Arzondo, L.M. Vazquez, A. Carella, J.M. Pastor, J.M. A low-cost, low- fiber -breakage, injection molding process for long sisal fiber-reinforced polypropylene. Polymer Engineering and Science 44 (9) 1766-1772 (Sep 2004). 

Izod impact strength is very important characteristic of the engineering plastics.The izod impact strength(notched,J/m) of injection molded test pieces was 92 J/m which was lower than , but higher than those of poly(butylene terephthalate) and glass fiber reinforced . 

Gears fabricated from carbon fiber reinforced nylon thermoplastic molding compound have been used in gearboxes of railway engines. 

WITH the easy-processing properties in the liquid crystalline phase, main-chain TLCPs have been widely used as high-strength fiber, fiber reinforcement, in situ reinforcement additive, and injection molded articles, etc, [ 1 -4]. The successful applications are quite dependent on the adhesion at interface of the liquid crystalline polymer and the conventional engineering resin, which is indeed affected by surface tension and/or interfacial tension between the two phases [1-2],... 

In many engineering applications short glass fiber reinforcement is added to the material. This has the advantage of increasing the strength and modulus of the material. As the material flows into the mold, the fluid deformation and interaction with other fibers alters the orientation of the fibers. The final orientation state will depend on the processing history of the material and may lead to highly anisotropic material properties. 

Traditionally, material design requirements that suit such demanding end-use applications have been limited within the domain of engineering plastics based on polyamide 6 or 66, polyester alloys, and polyacetal type resins. However, as described in Chapter 1, glass fiber-reinforced polypropylene (GFRP) composites continue to gain a market share in automotive molded parts. 

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