Vinylon

Vinal fibers, or poly(vinyl alcohol) fibers, are not made in the United States, but the fiber is produced commercially in Japan, Korea, and China where the generic name vinylon is used. These materials are the subject of this article (see also Vinyl polymers, vinyl alcohol polymers). 

China s textile raw material needs by 1985 will amount to at least 4.26 million M.T. In synthetics, China is committed to developing polyester fibers as its primary manufacture, with output for 1985 targeted at 1.5 MMT (equivalent to the 1979 Japanese level of synthetic production. The present Chinese output is only 326,000 M.T.) Limited quantities of nylon, polypropylene, vinylon, acrylic and polyester fibers are already produced. 

The major producers of VAM and VAM-based polymers include, but are not limited to, BP of the UK and Wacker Chemie of Germany. Celanese Chemicals, Dow Chemical Corp., DuPont and Millenium are important USA-based producers. In Asia, Kuraray, Nippon Gohsei and Showa Denko of Japan Dairen Chemical and Asian Acetyls of Taiwan and Shanghai Petrochemical and Sichuan Vinylon Works of China produce VAM and their polymers. These regions are also the major markets for the different products obtained from PVAc and its derivatives. 

The nonyl aldehyde coproduct of the azelaic half aldehyde is a useful intermediate after being transformed into the corresponding alcohol, acid, or amine, it is a raw material for plastics. Several years ago, I. Sakurada, Kyoto University, the inventor of Vinylon, found that when nonyl aldehyde is used instead of formalin for acetalization of poly (vinyl alcohol), the properties of Vinylon yarns are considerably improved, especially in elastic recovery. 

Fig.1. Synthetic scheme of Vinylone S. The first synthetic fiber in Japan...

Yarns which have a composition corresponding with polyvinyl alcohol, known as Vinylon, have been used with some success in Japan. The polymer is soluble in water and is therefore of no textile value. Treatment with formaldehyde, however, builds ether linkages between adjacent carbon atoms attached to hydroxyl groups as shown in the equation ... 

The filaments arc stretched, and dried at 210 to 22(. C in order to impart sufficient resistance to water to make it possible to treat them with formaldehyde and sulphuric acid, in aqueous solution, at 75 C, when about 40 per cent of the hydroxyl groups react with the formaldehyde. Vinylon withstands boiling water and softens at about 200 C. It has a dry strength of 3-2 g per denier and 2-3 g per denier when wet, with a 28 per cent elongation at break. 

A process has been developed in Japan for producing fibers from poly(vinyl alcohol). The polymer is wet spun from a warm aqueous solution into a concentrated aqueous solution of sodium sulfate containing sulfuric acid and formaldehyde, which insolubilizes the alcohol by formation of formal groups (see below). These fibers are generally known as vinal of vinylon fibers. 

Poly(vinyl alcohol) -(—CH2CH ) Vinylon, Kuralon,... 

Nihon Vinylon Company (now Nitivi) began the production of filament yarn by the dryspinning process in 1964. Aminoacetalized PVA was used as the starting material to improve... 

FIGURE 4.23 Biodegradability of water-soluble vinylon K-II fibers after solubilized in water. (From Ohmori, A., Sakuragi, I., and Onodera, M., Sen-i Gakkaishi, 55, 418, 1999.)... 

Although the dyeability of both polyvinyl chloride fiber and regular vinylon is difficult or not satisfactory, polychlal fiber is dyeable with various kinds of dyes. Some physical properties of polychlal, vinylon, and polyvinyl chloride fibers are shown in Table 4.28. All fibers listed in the table are commercial products in Japan [141]. 

Polyvinyl chloride fiber has a strong resistance to inorganic chemicals, and it swells or dissolves only in a limited number of organic liquids. Weather resistance is also high when it is compared with that of other synthetic fibers such as nylon 6 and vinylon. 

Positive—Glass, Nylon 6,6, Nylon 6, Wool, Silk, Viscose staple, vinylon, Acrylan, Steel, Cotton Negative—Orion, Acetate rayon, Dynel, Saran, Rhovyl, Rubber... 

FIGURE 4.33 Change in the ratio of vinylon used for industrial applications. 

Since the completion of the first edition of Fiber Chemistry, remarkable progress has taken place in the industrial applications of vinylon. The health hazards of asbestos, which had been used as reinforcement materials in cement, led to the search for an alternative cement-reinforcement fiber. Among the many fibers tested, vinylon showed the most superior performance. Figure 4.34 shows the flexural strengths of the slate in the presence... 

Kitano, T. Kataoka, T. Nagatsuka, Y. (1984). Dynamic Flow Properties of Vinylon Fibre and Glass Fiber Reinforced Polyethylene Melts. Rheologica Acta, Vol.23, No.4, PP.408A16 ISSN 0035-4511... 

Vinol 523, 540 t[Air Prods. http //www.airproducts.com], Vinylon [Aicello Chemical Co Ltd http //www.aiceiio.co.jp]... 

Vinylon. See Polyvinyl alcohol Vinyloxy-cyclohexane. See Cyclohexyl vinyl ether... 

Polyvinyl alcohol (super and fully hydrolyzed) Rhodoviol 4/125 Sicovol 1 Solublon KA Tubigum RPA 130 Tubigum RS Fluessig Unisize HA-25 Vinex 1003 Vinex 2019 Vinex 2025 Vinex 2034 Vinex 2144 Vinex 5030 Vinol 523, 540 Vinylon 9002-90-8... 

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