Protein fibers Properties

Blending with corn zein protein can strengthen soy protein fibers. Soy—zein blends exhibited increased tenacity and more flexibility. As with soy protein fibers, properties of blended fibers changed with water activity, but the properties were always better with blended fiber systems (Zhang et al., 1997). 

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... 

Most plant and animal materials contain natural fibers that have been concerted into useful fibers for thousands of years including ropes, building materials, brushes, textiles, and brushes (Table 18.6). Animal protein fibers such as wool and silk are no longer competitive with synthetic fibers with respect to cost but are still often utilized in the production of high-end rugs. Some of these rugs are hundreds of years old yet retaining their color and physical properties. 

Proteases modification of protein fibers (wool), improvement of felting properties, improvement of printability of wool, degumming of silk... 

Because natural silk, as a protein fiber of animal origin, resembles wool in its chemical structure, it can be dyed with most of the classes of dyes used for wool. The choice of dyes depends essentially on the fastness properties required. 

To gain a better understanding of the effect of protein fiber type, dye, and mordant on sunlight and burial weathering processes, we dyed wool and silk with three phenolic dyes (found as major components in natural dye mixtures extracted from various plant sources) and post-mordanted samples of the dyed fabrics with five representative metal salts. We then exposed the unmordanted and the dyed-mordanted samples to simulated sunlight or soil burial and measured the differences in the color and tensile properties that resulted from these treatments. 

Little recent work has been reported on the water relations and sw elling properties either of native elastin or elastin that has been isolated by various procedures or treated with enzymes or hydrolytic reagents. This is to be deplored since the study of the hydration of a protein fiber is often a sensitive means of revealing the pattern of lateral bonds which lends structural stability. A comparison of the hydration of elastins derived from different animals, or different tissues of the same animal, would be particularly valuable since the methods are relatively insensitive to the preseruic... 

M. G. M. Pryor. Pro. Biophys, and Biophys. Chem. 1, 216-68 (1950). Mechanical properties of protein fibers, muscles. 

Several other polyamides are derived from natural poly(amino acids) that are subject to a subsequent synthetic treatment. Examples are casein, groundnut protein fiber, and zein, which after a treatment with formaldehyde led to new materials with better mechanical/solubility properties. For example, casein is a mixture of several proteins that forms 3% of milk (as casein calcium salt). Casein can be fractionated into simpler proteins designated as a, 3, y, and k [37]. The amino acid content of casein is similar to... 

Orientational order plays an important role in solid polymers. It is often induced by industrial processing, for example in fibers and injection- or compression-modulated parts. In polymers with liquid-crystalline properties of the melt or solution, the anisotropies generated by the flow pattern are particularly pronounced. In order to improve the mechanical properties of polymer fibers or films, the degree of orientation is intentionally enhanced by drawing. At the same time, anisotropy of mechanical properties can result in low tolerance to unfavourably directed loads. In many liquid-crystalline polymers, in the mesophase near the transition to the isotropic phase, electric or magnetic fields can induce macroscopic orientational order [1]. Natural polymers such as silk protein fibers, which are biosynthesized and spun under biological condition, also have good mechanical properties because of their ordered structure [2]. 

Soy protein was one of a number of proteins that were used to produce reg protein textile fibers in the late 1930s and 1940s. The discovery of regenerated protein fibers from casein is attributed to Todtenhaupt in 1904, but it was Parretti, who in 1935 successfully developed, patented, and produced a textile fiber with wool-like properties from soy protein. In the United States, soy protein textiles and felt materials were explored as replacements for wool, felt, and fur (Hartsuch, 1950 MoncriefF, 1975). In 1939, the Japanese reportedly produced about 450,000 kg (1 million lb) of soy protein fiber (Conner, 1989). The first U.S. patents for soy fibers were granted to T. Kajita and R. Inoue in 1940 (Kajita Inoue, 1940). 

The pH at which a protein or particle has an equivalent number of total positive and negative charges as determined by proton exchange is the isoionic point. The pH at which a protein or a particle does not migrate in an electric field is called the isoelectric point. The isoionic point is a whole fiber property of hair and is reflected in the equilibrium acid-base properties of the total fiber the isoelectric point is related to the acid-base properties of the fiber surface. 

Thus, important optical properties of the cornea may be deduced from the relationship between swelling pressure and tissue hydration. An electromicrograph of osmiumtetroxide stained rabbit cornea is shown in Figure 1. At normal hydration the protein fibers are in a periodic array. Figure 2 shows a swollen cornea substantial fluctuations occur in neighbor - neighbor distances between the protein fibers, and the array is no longer of the crystaline lattice type. 

After treatment with water, there was a weight loss of 9.27% for the non-treated fiber, indicating that a small amount of soluble extractives is removed with water. The soluble extractives removed by water are typically carbohydrates, gums, proteins and inorganic salts. Santiago [24] shows that hot water treatment removes part of the waste material in the coconut fiber, without removing the internal components of the fiber, thus avoiding alterations of the fiber properties. 

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. 

Liivak, O., Blye, A., Shah, N., Jehnski, L.W., 1998. A microfabricated wet-spinning apparatus to spin fibers of silk proteins. Structure—property correlations. Macromolecules 31 (9), 2947-2951. 

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