Wool fiber, composition

Hydrocarbon and mineral oils are used to coat cellulose, glass, asbestos, or mineral wool fibers. Composition of the plasticizer and fibers is then mixed with the polymer matrix, with which the plasticizer is also compatible. As a result, ordinary polymer mixing equipment such as mills and internal mixers can be used, with economically acceptable mixing times under mild conditions, to prepare homogeneously dispersed fibre-polymer compositions. Frequently this process is used to obtain homogeneous dispersion of fibers but also to protect fibers or glass bubbles from mechanical damage. 

Kelly, F.M. and Johnston, J.H. (2011) Colored and functional silver nanoparticle-wool fiber composites. ACS Appl. Mater Interfaces, 3,1083-1092. 

Wool fibers have a very complex morphological stmcture. They can be considered as biological composite materials, in which the various regions are both chemically and physically different (87). Fine wool fibers contain two types of cell those of the internal cortex and those of the external cuticle. 

The hair fibers derived from furry mammals are mainly made up (over 80%) of the structural protein keratin. The distinction between wool and hair is not compositional, but related to size wool fibers are generally fine and short, whereas those of hair are usually thicker and longer. The molecule of keratin consists essentially of a combination of amino acids about 18 amino acids make up the keratin molecule (see Textbox 67). The nature of the amino acids, their relative amounts, and their sequence and arrangement within the molecule of keratin vary from one animal species to another but are characteristic of any variety of wool or hair (Asquith 1977) (see Table 89). 

Sources Data on E glass composition are from Loewcnstein (1973), Table vi/i glass insulation and wool composition data come from Mohr and Rowe (1978), Table 5-1 continuous textile fiber composition data are from Gagin (1980). 

Naphthas are also employed as solvents in the manufacture of printing inks, leather coatings, diluents for dyes, and degreasing of wool fibers, polishes, and waxes, as well as rust- and waterproofing compositions, mildew-proofing compositions, insecticides, and wood preservatives. 

Amino Acid Compositions of Components of Wool Fibers ... 

Eastes W., Potter R. M., and Hadley J. G. (2000b) Estimating rock and slag wool fiber dissolution rate from composition. Inhalat. Toxicol. 12, 1127—1139. 

By analogy with the effects of malnutrition and sulfur enrichment on the high-sulfur proteins of the keratin-associated proteins in wool fiber [44,45], these effects of a lower cystine content in hair are probably a result of a decreased synthesis of the sulfur-rich proteins because of malnutrition. Studies of the effects of diet in persons suffering malnutrition (i.e., protein deficiencies) show that diet supplementation can influence the protein composition of human hair. However, such effects have only been demonstrated among persons suffering from severe malnutrition and never among healthy persons on a normal diet see the section on the keratin-associated proteins of human hair later in this chapter. 

Leeder and Rippon [85] have analyzed the lipid composition of wool fibers after removing surface grease. Continued extraction with solvent removed the beta layers evidenced by electron microscopy however, the extract contained free cholesterol and free fatty acid and triglycerides but negligible quantities of phospholipid normally associated with biological membrane lipids. Koch [86], in his work with internal lipid of human hair, did not report significant quantities of phospholipid. These lipid-protein layers of hair are most likely related structurally to those of the epicuticle. 

Similar isoelectric points for hair and wool fiber are to be expected because chemical compositions of the cuticle are similar and because both fibers show similar dye-staining characteristics. Cuticle from both fibers stains more readily with cationic dyes than with anionic dyes [96], whereas the cortex stains readily to anionic dyes [121]. 

Owing to the method of contact-angle or surface-energy measurement, the surface of wool necessarily includes the region between cuticle cells in addition to the cuticle itself Horr has further suggested that vapor adsorption due to capillary condensation may occur at the fiber cuticle scale edges, and that the phenomenon may contribute to the above interpretation that the wool surface is not entirely methyl. Horr also found that the possible composition of the wool fiber surface may even vary depending on the liquid with which it is in contact (e.g., water or methylene iodide). 

By definition, the so-called membranes obtained from the CMC result after the treatment of wool fibers with degradative reagents such as acids, alkalis, proteolytic enzymes, and reducing and oxidizing agents [16,84,178,179]. Hence the resistant membranes of cortical and cuticle cells must be regarded as residues from these treatments or combinations of these treatments. Factors such as preferential extraction during the various treatments and the different experimental parameters of different studies have obviously led to variations in the descriptions of resistant membrane compositions. 

Research on plasma treatment on wool fiber as a pretreatment was started in 1956 (Rakowski, 1997). Plasma-treated wool fiber displays improved antifelting property, dye-ability, and surface wettability. The plasma treatment can alter the surface morphology and chemical composition, but the effect depends greatly on the plasma gas used, system pressure, discharge power, and also treatment lime. Plasma treatment on wool fiber is a dry process in which fiber alteralion is concentrated on the fiber surface and less damage is caused to the bulk fiber. This is a major advantage of plasma treatment on wool fiber. 

Cl 2-15 pareth-4 coemuisifier, wax emulsions PEG-4 castor oil PEG-6 castor oil coemuisifier, wool fiber processing PEG-25 tallowamine coffee compositions, synthetic Furfuryl mercaptan coffee substitute... 

The wood fiber has a scaly structure (Figures 30-4 and 38-11). It consists of two parts of differing chemical composition and different properties—the paracortex and the orthocortex. Consequently, the wool fiber is, technologically, a bicomponent fiber (see Chapter 38). The cortices are, in turn, made up of bundles of cortex cells which have a cell nucleus at the center. Each cortex cell consists of microfibrils which are arranged about a core in what is known as a matrix of very sulfur-rich proteins. Each microfibril has 11 of what are called protofibrils, nine of which surround a central pair. Each protofibril consists of two to three a helices. 

A. O Donnell, M. A. Dweib and R. P. Wool, Natural fiber composites with plant oil-based resin . Compos Sci Technol, 2004, 64,1135 5. 

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