Acrylic fibers Properties

Lulay [351] has compared acrylic fiber properties against other fibers, and the comparisons are shown in Table 12.18. A scale of five (highest or best) to one (lowest or poorest) was used to assess properties. The basic properties of the various fibers have been translated to end-use performance, and the importance of these performance properties to the consumer for apparel has been segregated into three categories highly desired, somewhat desired, and... 

Chem. Descrip. Lauryl dimethyl benzyl ammonium chloride Ionic Nature Cationic CAS 139-07-1 EINECS/ELINCS 205-351-5 Uses Surfactant retarder for acrylic fiber Properties Liq. 50 and 80% solids Ablumine 1214 [Taiwan Surf.]... 

Uses Surfactant retarding agent for dyeing acrylic fibers Properties Liq. 

Uses Softener, finishing agent, and antistat for acrylic fibers Properties Lt. yish. paste paste 30% cone. 

Uses Disinfectant for dairy, food processing, restaurant, brewing, and bottling industries retarder in dyeing of acrylic fibers Properties Pale yel. liq, dens, 0,98 g/cm vise. 120 cs cloud pt. < 0 C pH 7.0-9.5 (5% aq,) 50.0 1.5% act, in water Empigen BCF 80 [Huntsman Perf, Prods.)... 

Chem. Descrip. Fatty polyamide derivatives Ionic Natum Cationic Uses Softener for nylon and acrylic fibers Properties Liq. 

Chem. Descrip. Quat. ammonium salt Ionic Nature Cationic Uses Leveling agent for acrylic fibers Properties Liq. 

Acrylic fibers are characterized by having properties similar to wool and have replaced wool in many markets such as blankets, carpets, and sweaters. Important properties of acrylics are resistance to solvents and sunlight, resistance to creasing, and quick drying. 

Cellulosic, polyester, and acrylic fibers lubricated with a surfactant-based oiling composition containing an organic phosphorus ester neutralized with an amine showed less pilling, good antistatic properties, and anticorrosiveness. The phosphorus ester salts were hexyl phosphate trimethylamine salt, dodecamethy-lene caproate phosphonate ethylamine salt, and polyethylene glycol dodecyl ether phosphate dimethylamine salt [262]. 

Recently, nitrilases have been applied to polymer modification, specifically to the modification of polyacrylonitrile (PAN). Nearly 3 x 106 tons of PAN are produced per annum and used in the textile industry. However, there is a great need to improve moisture uptake, dyeability with ionic dyes, and feel of this acrylic fiber. The cyano moieties of PAN have been successfully modified to carboxylates with the commercial Cyanovacta nitrilase, thus enhancing the aforementioned properties of PAN [98]. Nitrilase action on the acrylic fabric was improved... 

Acrylonitrile is a colorless, liquid, man-made chemical with a sharp, onion-or garlic-like odor. Acrylonitrile is used mostly to make plastics, acrylic fibers, and synthetic rubber. Because acrylonitrile evaporates quickly, it is most likely to be found in the air around chemical plants where it is made. Acrylonitrile breaks down quickly in the air. It has been found in small amounts in the water and soil near manufacturing plants and hazardous waste sites. In water, acrylonitrile usually breaks down in about 1 to 2 weeks, although this can vary depending on conditions. For example, high concentrations of acrylonitrile (such as might occur after a spill) tend to be broken down more slowly. In one case, measurable amounts of acrylonitrile were found in nearby wells 1 year after a spill. Further information on the properties and uses of acrylonitrile and how it behaves in the environment may be found in Chapters 3, 4, and 5. 

Cellulose triesters, moisture properties of selected, 5 416t Cellulose trinitrate, 5 396 Cellulose valerate(s), 5 419 moisture properties, 5 416t Cellulose x, 5 373, 378-379 8 21 Cellulose xanthate, 4 716 5 383 20 559 Cellulosic-acrylic fibers, dyeing, 9 201-202 Cellulosic fiber blends, dyeing, 9 199-202 Cellulosic fiber—nylon blends, dyeing, 9 202 Cellulosic fibers, 18 96... 

Because of the repulsion of the cyanide groups the polymer backbone assumes a rod-like conformation. The fibers derive their basic properties from this stiff structure of PAN where the nitrile groups are randomly distributed about the backbone rod. Because of strong bonding between the chains, they tend to form bundles. Most acrylic fibers actually contain small amounts of other monomers, such as methyl acrylate and methyl methacrylate. As they are difficult to dye, small amounts of ionic monomers, such as sodium styrene sulfonate, are often added to improve their dyeability. Other monomers are also employed to improve dyeability. These include small amounts (about 4%) of more hydrophilic monomers, such as -vinyl-2-pyrrolidone (Equation 6.69), methacrylic add, or 2-vinylpyridine (Equation 6.70). 

Improved Comfort Properties. Wear comfort generally means cotton-like properties, The ability lo absorb moisture from the skin and ihe softness of cotton fabrics are considered to be the two key properties for comfort. The extremely line denier of cotton fibers accounts for its softness. Both properties can be achieved in acrylic fibers. Improved moisture retention can be achieved by incorporating hydrophilic comonomers that decrease ultimate fiher density, by modifying the fiber spinning process, ur by using after-treatments such as modified finishes. 

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. 

Acrylic fibers possess a property that made it possible for them in the late 1950s and early 1960s to find immediate, even spectacular, acceptance in the knitted sweater field, until then dominated by wool. When acrylic fibers, normally in the form of a heavy tow, are hot-stretched (e.g., by being drawn over a hot plate and then cooled under tension), they are converted to a labile state. Upon immersion in hot water, such fibers will contract considerably, but not to their prior unstretched length. In practice, this characteristic is used to... 

Benzodiazepines and 3//-1,5-benzodiazepines are important classes of compounds because of their interesting pharmacological properties. They show anticonvulsant, antianxiety, analgesic, sedative, antidepressive, hypnotic, antiinflammatory activity and also potent inhibitor of HIV-1 reverse transcriptase. Besides their biological relevance, benzodiazepines have also found application as dyes for acrylic fibers [163]. 

Acrylics. Acrylics are produced by the polymerization of acrylonitrile. They have a chemical structure essentially comprising the repeating unit, [ —CH2—CH(CN)—]n, with up to 15 percent of the polymer comprising one or two other monomeric units. As comonomers, vinyl acetate and an acrylate or methacrylate ester is used to vary the properties of the polymer for both ease of processing into a fiber and for improved fiber properties [8]. 

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