Short fibers fiber-polymer systems

As one might expect, any fiber-polymer system is unique, not only because of the differences in the respective properties of the components, but also because the fiber surface properties and the polymer chemistry have important effects. Not all aspects are yet understood and any generalization would indeed be abusive. A clear demonstration of this fact is offered when comparing the effect of a given type of short glass fiber (E-glass), at constant loading (30%) in different thermoplastics (Table 7.2). 

Fakirov, S. and Fakirova, C., Direct determination of the orientation of short glass fibers in an injection-molded polyethylene terephthalate) system, Polym. Composites, 6, 41 (1985). 

The principles of compounding were reviewed earlier in this text and cover the fundamental characteristics of polymers, filler systems, and the basics of vulcanization in the context of compound development for tire applications. A compound formulation consists of four basic components the polymer network, the filler or particulate reinforcing system, the stabilizer system, and the vulcanization system (Figure 14.21). In addition a series of secondary materials such as resins, processing oils, and short fiber reinforcements may be included in a formula (Duddey, 2004 Rodgers and Waddell, 2004 Long, 1985). Elastomers used in radial tires are basically of four types ... 

On the other end of the scale are the conducting and semiconducting polymers. Several types exist. For example, conducting fillers may be added, such as short metallic fibers that touch each other or carbon black. Alternately, an ionic polymer may be employed, or a salt may be added to the polymer. Conductivity in the latter systems depends on the moisture content of the polymer. 

Zihlif and Ragosta produced short (1-3 mm) BF-reinforced polystyrene (PS) composite plates and found that the strength of the composite went through a maximum whereas both Young s modulus and the impact resistance increased monotonically with increasing BF content. Bashtannik et alP investigated the fiber-matrix interfacial adhesion in BF composites with high density polyethylene (HDPE) matrix. It was found that the properties of BF-reinforced polymer composites were much more sensitive to the BF surface treatment than traditional fiber-reinforced systems. 

Tucker, C.L., Advani, S.G. Processing of short-fiber systems. In Advani, S.G. (Ed.) Flow and rheology in polymer composites manufacturing, pp. 147-202. Elsevier, Amsterdam (1994)... 

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