Nylon polyurethane

In the second quarter of the twentieth century, with the development of poly(vinyl chloride), nylon, polyurethane, and other polymers, many new and improved leather-like materials, so-called coated fabrics (qv), were placed on the market. Shortages of leather after World War 11 led to the expansion of these leather-like materials ("man-made" leathers) to replace leather in shoes, clothing, bags, upholstery, and other items. DurabiUty and waterproof quahties superior to leather made coated fabrics advantageous, in spite of imperfection in breathabihty and flexibiUty. Demands for shoes, clothing, and other items are stiU increasing due to growing world population and urbanization. 

Polyesters, polyurethanes Polyesters, nylons, polyurethanes Polypropylene, LDPE, PMMA, poly(alpha-methylstyrene) Polybutadienes, polyisoprene... 

Styrene-methyl methacrylate copolymer PVC sheets Aramid nylon Polyurethane foam LDPE resin Ethylene-propylene... 

Several high-performance or engineering polymers, such as the polyfluo-rocarbons, acetals, ABS, nylons, polyurethanes (PUs), silicones, and phos-phazenes, have been described in previous chapters. Several elastomers, such as butyl rubber, EPDM (elastomeric terpolymer from ethylene, propylene, and a nonconjugated diene), and Neoprene, which play a vital role in engineering, and a host of classic thermosets should also be considered high-performance polymers. The properties of other high-performance polymers are described in this chapter. 

By March 1, 1957, the ami noethylation of the following materials and compds had been achieved by the Wyandotte Chemicals Corp cellulose, cellulose derivatives, regenerated c e 1 lu los e, 2-hydroxymethy 1-2-nitro-1,3-pro-panediol, nylon, polyurethane, polyvinyl alcohol, polyvinylchloride, protein(wool), starch and toluene diisocyanate... 

Polyolefins. Ultra-High-Molecular-Weight Polyethylene.TIus is easily made by conventional low-pressure coordination polymerization. Hercules Hi-fax 1900 has a molecular weight of 2.5-5.0 million. Its outstanding properties are low coefficient of friction (0.11) abrasion-resistance superior to nylon, polyurethane, and steel unbreakable in the Izod notched impact test and high resistance to most inorganic and many organic chemicals. 

Synthetic stocks are gradually replacing the traditional wooden stock due to their cheapness, ease of manufacture, lighter weight, and wear ability, and are claimed to be more stable and easier to maintain than wooden stocks. Materials such as nylon, polyurethane, fiberglass, Kevlar reinforced with fiberglass or carbon fiber, or thermoplastic resin reinforced with glass and ceramics may be used. The stocks may be hollow, or have a hollow filled... 

Strong Polar Interactions and Hydrogen Bonds, Complex Form, but also Short Range I-10 kcal/mdle Nylons Polyurethanes ... 

Oxidative degradation can also occur in other polymers including natural rubber, polystyrene, polypropylene, nylons, polyurethanes, and most natural and naturally derived polymers. With the exception of fluo-ropolymers, most polymers are susceptible to oxidation, particularly at elevated temperature or during exposure to ultraviolet hght. Oxidation usually leads to increasing brittleness and deterioration in strength. 

Precision of FIT and SIT measurements is usually fair. ASTM D 1929-96 lists examples for several different plastics among them are PVC, polystyrene, nylon, polyurethane, and phenol-formaldehyde resin (see Tables 14.11 and 14.12), tested by seven laboratories, using three replicates of each material. Repeatability in this case is the difference (in°C) between two averages, each one determined from three specimens of identical test material, using the same apparatus by the same analyst within a short time interval. 

The most common use for nitric acid is in the manufacture of ammonium nitrate, which, in turn, is used primarily as a fertilizer. About three-quarters of all nitric acid produced in the United States is used in fertilizers. The second most important application, accounting for about 10 percent of all nitric acid produced, is in the production of adipic acid [C00H(CH2)3C00H], used in the manufacture of nylon, polyurethanes, and other synthetic plastics. Nitric acid is also used to make a variety of metal nitrates and for the cleaning of metals. Small amounts of the compound are used for a variety of other applications, including ... 

During World War II, the U.S. military finds a number of uses for nylon, polyurethanes, polystyrene, percholorates, and silica gel. 

Polymer characterization is an important use of NIR spectrometry. Polymers can be made either from a single monomer, as is polyethylene, or from mixtures of monomers, as are styrene-butadiene rubber from styrene and butadiene and nylon 6-6, made from hexamethylenediamine and adipic acid. An important parameter of such copolymers is the relative amount of each present. This can be determined by NIR for polymers with the appropriate functional groups. Styrene content in a styrene-butadiene copolymer can be measured using the aromatic and aliphatic C—H bands. Nylon can be characterized by the NH band from the amine monomer and the C=0 band from the carboxylic acid monomer. Nitrogen-containing polymers such as nylons, polyurethanes, and urea formaldehyde resins can be measured by using the NH bands. Block copolymers, which are typically made of a soft block of polyester and a hard block containing aromatics, for example, polystyrene, have been analyzed by NIR. These analyses have utilized the... 

Polyesters, nylons, polyurethanes, silicones, epoxies, phenolics, acrylics... 

High strength bonds to polyester, nylon, polyurethane and metals. 

Dimethylformamide (DMF) n. A colorless and very active solvent for PVC, nylon, polyurethane, and many other resins and elastomers, with fairly low volatility. Its strong solvent power makes it useful as a solvent booster in coating, printing, and adhesive work, and in paint strippers. Because it is toxic and readily absorbed through the skin, DMF must be handled, and disposed of, with care. 

Reaction injection molding Nylon, polyurethane (thermoset), epoxy, polyester... 

Condensation polymers are formed by the reaction of bifunctional or poly functional molecules, with the elimination of some small molecule (such as water, ammonia, or hydrogen chloride) as a by-product. Familiar examples of synthetic condensation polymers include polyesters (Dacron, Mylar), polyamides (nylon), polyurethanes, and epoxy resin. Natural condensation polymers include polyamino acids (protein), cellulose, and starch. The process can be represented as follows ... 

Lastly, synthetic varieties of textiles are present primarily in apparel and are either petroleum-based or blends with natural fibers. Polyester fibers, aramid fibers, acrylics, nylon, polyurethane, olefins (hydrophobic), polylactide (hydrophilic), milk protein-based fibers, and carbonization-based fibers all constitute synthetics which require some level of surface-modification. This includes nonwovens, structures bonded together by entangling fiber or filaments mechanically, thermally, or chemically. 

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