Fiber properties, role

The / -transition is a key feature and trademark in silks (Craig, 2003), whether the final product (Fig. 7) will be a high-performance fiber or will have other functions (Craig, 1997). The role, functionality, and diversity of each silk raise the interesting question whether selection pressures on the final fiber properties are mirrored (at, ultimately, the molecular level) in the precursor liquid proteins. Figure 8 shows SRCD spectra of six of the... 

Figure 8-32) other fiber properties (friction, stiffness, etc.) play a more important role in hair behavior. However, when curvature is high (hair is very curly—Figure 8-32), this fiber property dominates other fiber properties and controls hair effects. 

Barone and Schmidt (2005) reported on the use of keratin feather fiber as a short-fiber reinforcement in LDPE composites and showed that protein fibers have good resiliency and elastic recovery. Besides protein fibers have higher moisture regain and warmthness than natural ceUulosic fibers properties, all related to its possible use in earth material. The keratin feather fiber for these tests was obtained from chicken feather waste generated by the U.S. poultry industry (Galan-Marm et al. 2010). Clearly, water can play a very important role in these materials that can be elucidated using NMR spectroscopy however, this aspect was poorly studied. 

In addition to their role in composites, high performance fibers are also found in coated and laminated textile products, three-dimensional fabric stmctures, multifunctional property improvement, and intelligent or self-adaptive materials. 

Several physicochemical properties of dietary fiber contribute to its physiological role. Water-holding capacity, ion-exchange capacity, solution viscosity, density, and molecular kiteractions are characteristics determined by the chemical stmcture of the component polysaccharides, thek crystallinity, and surface area. 

Porous carbon fiber-carbon bmder composites are a class of matenals that are not widely known, yet they fulfill a vital role in the RTG space power systems, and show considerable potential for other uses in light absorption or gas adsorption applications. These applications are enabled through the unique combmation of physical properties exhibited by the porous carbon fiber-carbon binder composites Perhaps the most significant of its physical attributes is the open, yet rugged, form of the material which contributes significantly to its utility m the fields of... 

Fibers are often regarded as the dominant constituents in a fiber-reinforced composite material. However, simple micromechanics analysis described in Section 7.3.5, Importance of Constituents, leads to the conclusion that fibers dominate only the fiber-direction modulus of a unidirectionally reinforced lamina. Of course, lamina properties in that direction have the potential to contribute the most to the strength and stiffness of a laminate. Thus, the fibers do play the dominant role in a properly designed laminate. Such a laminate must have fibers oriented in the various directions necessary to resist all possible loads. 

One of the interesting properties of PBPCP [187] was its fast heat dissipation characteristics and so it was tested by the well-known oxy-acetylene panel test (ASTM 285-70) for ablative materials. Figure 13 shows the survival of a flower for 100 s. kept on the 6.35-mm asbestos fiber-reinforced hexamine-cured panel. The ablation rate value of this material was 3.2 x 10 in/s in comparison with 3.6 x 10 in/s for asbestos-phenolic. As the char content of PBPCP was only 27% compared with 60% for conventional phenolics, mechanisms involving transpiration processes rather than heat blocking by char formation might be playing a greater role in this case [188]. 

The role of the matrix is to protect the filler from corrosive action of the enviroment and to ensure interactions between the fibers by mechanical, physical and chemical effects. The mechanical properties of fiber composites are dependent on the mutual position of the fibers in the monolithic materials. 

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