Synthetic fiber acrylic

Acrylic fibers present less of a problem with static and cling than most other synthetic fibers. Acrylics are naturally somewhat hydrophilic and tend to dissipate static charge more readily than other synthetic fiber types. Antistatic properties have been improved, however, by making the fibers hygroscopic with hydrolyzing and cross-linking agents [498,499]. 

Melt Spinning. Compared to most other synthetic fibers, acrylics have always had the disadvantage of extra process steps and cost incurred because... 

Acrylonitrile, C3H3N, is the starting material for the production of a kind of synthetic fiber (acrylics). It can be made from propylene, C3H5, by reaction with nitric oxide, NO. 

ABS, POM, PC, PE, PP, PS, flexible and rigid PVC synthetic fibers (acrylic, polyester, polyamide, and acetate), polyurethane foam, paints... 

Acrylonitrile (AN), C H N, first became an important polymeric building block in the 1940s. Although it had been discovered in 1893 (1), its unique properties were not realized until the development of nitrile mbbers during World War II (see Elastomers, synthetic, nitrile rubber) and the discovery of solvents for the homopolymer with resultant fiber appHcations (see Fibers, acrylic) for textiles and carbon fibers. As a comonomer, acrylonitrile (qv) contributes hardness, rigidity, solvent and light resistance, gas impermeabiUty, and the abiUty to orient. These properties have led to many copolymer apphcation developments since 1950. 

Synthetic fibers such as polyester and acrylic engineering polymers such as acrylonitrile butadiene styrene (ABS) ... 

Acrylic fibers are a major synthetic fiber class developed about the same time as polyesters. Modacrylic fibers are copolymers containing between 35-85% acrylonitrile. Acrylic fibers contain at least 85% acrylonitrile. Orion is an acrylic fiber developed by DuPont in 1949 Dynel is a modacrylic fiber developed by Union Carbide in 1951. 

Acrylic fiber breaking strength ranges between 22,000 and 39,000 psi and they have a water absorption of approximately 5%. Dynel, due to the presence of chlorine, is less flammable than many other synthetic fibers. 

DuPont continued their leadership role in synthetic fibers by commercializing acrylic fibers (Orion) in 1950. They did a repeat performance in 1-953 with a polyester called Dacron. The big four fibers—Nylon 6, Nylon 66, acrylics, and polyester—now account for most of the synthetic production and about half of the fiber production of all kinds, including cotton, silk, and wool. 

The entire spectrum of inorganic fibers can be divided into two classes, based on differences in the crystallinity of the solids (Ray, 1978). Synthetic fibers have been known as man-made mineral fibers (MMMF) and manmade vitreous fibers (MMVF). But fibrous materials can be approached or divided in other ways. For example, in the Concise Encyclopedia of Chemical Technology (1985) the entry for chemical fibers includes both manmade and natural polymers, with the discussion centering on carbon-based compounds such as acetates, acrylics, and cellulose. Fibers of other inorganic compounds were not mentioned in the encyclopedia under this entry, but silica glass fibers were described under the heading Optical Fibers. ... 

Table 10.2 outlines the uses of acrylonitrile. One important use of acrylonitrile is in the polymerization to polyacrylonitrile. This substance and its copolymers make good synthetic fibers for the textile industry. Acrylic is the fourth largest produced synthetic fiber behind polyester, nylon, and... 

However, synthetic fibers (cellulosic and noncellulosic) increased much more rapidly in importance, with cellulosics booming between World Wars I and II and noncellulosics dominating after World War II, while all that time cotton showed only a steady pace in comparison. The more recent competition between the various fibers in the United States is given in Fig. 17.1. Nylon was originally the most important synthetic (1950-1971) but polyester now leads the market (1971-present). For a few years (1970-1980) acrylics were third in production, but since 1980 polyolefins have been rapidly increasing. Polyolefins are now second only to polyester in synthetic fiber production. Cotton, being an agricultural crop, certainly demonstrates its variable production with factors such as weather and the economy. It is an up-and-down industry much more so than the synthetics. 

The student should also review Chapter 1, Table 1.16, where the top polymer production is given numerically. Overall a 1.8% per year growth was recorded for 1990-2000 in synthetic fibers. A net decrease in the cellulosics of 3.6% per year shows their diminishing importance. Acrylics also decreased 3.9% annually in this period. The rising star is polyolefins, which increased 5.8% per year in the past decade. 

Sulfur dyes are used mainly for dyeing textile cellulosic materials or blends of cellulosic fibers (qv) with synthetic fibers such as acrylic fibers, polyamides (nylons), and polyesters. They are also used for silk (qv) and paper (qv) in limited quantities for specific applications. Solubilized sulfur dyes are used on certain types of leathers (qv). 

Orusev, T., Bauer, S. Popovski, P. (1973) Occupational exposure to acrylonitrile in a plant for production of acrylic synthetic fibers. God. Zb. Med. Fak. Skopje, 19, 445-449 (in Macedonian) [Chem. Abstr., 81, 29030tj... 

Practically all synthetic fibers can be printed with disperse dyes. Cationic dyes are used preferentially for acrylic fibers, and acid dyes and metal-complex dyes can be used for prints on polyamide fibers. The importance of printing with disperse dyes and the relative amount of different man-made fibers used for prints varies according to fashion and local requirements. Polyester fabrics alone or in combination with cotton are the most important. After precleaning, fabrics made from synthetic fibers must be heat-set to achieve dimensional stability and crease resistance. The usual setting conditions are 20-30 s at 190-210°C, and for texturized articles about 30°C lower. 

Acrylic fibers (PAC) are, together with PES and PA, the most important synthetic fibers [154], For methods of production and properties of PAC fibers see [96, pp. 629-642], To obtain fibers with satisfactory dyeing properties, anionic comonomers are used. In this way, the glass transition temperature Tg is lowered and anionic groups are available that can act as dye sites for cationic dyes. Thus, acrylic fibers are reliably and economically dyeable wth cationic dyes. 

Synthetic Fibers Nylon, Polyesters, Acrylics, Elastane.161... 

Synthetic fibers have been characterized by a resistance to degradation over forensically relevant timescales (Table 7.4). Nylon (polyamide), polyester, and acrylic fibers show considerable resistance to soil burial. Regenerated cellulose fibers (rayon viscose), however, share the vulnerability of natural cellulose to decomposition (Rowe 1997). However, they do show a higher degree of resistance to biodegradation compared with natural fibers or regenerated cellulose, with the exception of triacetate. 

The first noncellulosic (synthetic) fiber to be of major importance for textile apparel was nylon. In the United States, nylon 66 was commercially produced in 1939 (4). Nylon 6, another polyamide which is produced also on a large scale, was obtained on a pilot plant scale in the same year in Germany (5). Modacrylic and acrylic fibers were commercially produced in the United States in 1949 and 1950, respectively (4). Polyester fiber was invented in England in 1940 (1) and went into commercial production in the United States in 1953 (4). Polyester production is higher than that of any other man-made fiber at this time (Table II). 

The Japanese solution to chemical fiber overcapacities naturally involved MITI which pushed through a 17% cut in existing polyester, Nylon filament, and acrylic fiber capacities between 1978 and 1982. These were linear cuts, however, and did not restrict the range of synthetic fibers developed by each producer, contrary to the specializations that marked the second stage of Europe s approach. 

Microdenier Fibers. The first commercial production of microfiber in the United States was in 1989 by the DuPont Company. Today microfibers are produced in a variety of synthetic fibers (i.e., polyester, nylon, acrylic, etc.) A microfiber is a fiber that is less than one denier per filament. Yams made from microdenier filaments are able to give silklike hand to fabrics. 

Acrylamide with a demand of 200,000 tons year" is one of the most important commodities in the world. It is used for the preparation of coagulators, soil conditioners, stock additives for paper treatment, and in leather and textile industry as a component of synthetic fibers. Conventional chemical synthesis involving hydration of acrylonitrile with the use of copper salts as a catalyst has some disadvantages rate of acrylic acid formation higher than acrylamide, by-products formation and polymerization, and high-energy inputs. To overcome these limits since 1985, the Japanese company Nitto Chemical Industry developed a biocatalyzed process to synthesize... 

BURCOVEL C may be used on a wide variety of natural and synthetic fibers and blends Including cotton, nylon, polyester, acrylics, and polyester/cotton blends. It provides excellent softness, lubricity, and drapability. It has good resistance to discoloration from heat, ageing, and ultraviolet light. Unlike many other cationic softeners, it does not reduce the absorbency of fabrics treated with it. BURCOVEL C imparts antistatic and antidusting properties as well as softness. 

CNC Soft G-1 is a subtstantive cationic softener which imparts a soft, slick hand to synthetic fibers, but particularly for acrylics such as orIon, acrilan, etc. CNC SOFT G-1 can be applied from long or short baths in such equipment as becks, paddle and package machines. CNC SOFT G-1 is cold water soluble and can be added directly to the finish bath. 

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