Tire materials rayon

Pyrolysis produces three principal products - pyrolytic gas, oil, and char. Char is a fine particulate composed of carbon black, ash, and other inorganic materials, such as zinc oxide, carbonates, and silicates. Other by-products of pyrolysis may include steel (from steel-belted radial tires), rayon, cotton, or nylon fibers from tire cords, depending on the type of tire used. 

Jets for continuous filament textile yam are typically 1 cm diameter gold—platinum ahoy stmctures with 20—500 holes of 50—200 p.m diameter. Tire yam jets are also 1 cm in diameter but typicahy use 1000—2000 holes to give the required balance of filament and yam denier. Staple fiber jets can have as many as 70,000 holes and can be made from a single dome of ahoy or from clusters of the smaller textile or tire yam jets. The precious metal ahoy is one of the few materials that can resist the harsh chemical environment of a rayon machine and yet be ductile enough to be perforated with precision. Glass jets have been used for filament production, and tantalum metal is a low cost but less durable alternative to gold—platinum. 

These results may be of particular value especially in connection with studies of technical cellulose fibers and cellulose derivatives the above results may be of value for estimation of the state and structure of the material. The work of Fyfe and coworkers 1S,16) indicates that in microscrystalline rayon (cellulose II), hydrolyzed tire cord (cellulose III) and hydrolyzed rayon (cellulose IV) the identification of... 

The rubber stock, once compounded and mixed, must be molded or transformed into the form of one of the final parts of the tire. This consists of several parallel processes by which the sheeted rubber and other raw materials, such as cord and fabric, are made into the following basic tire components tire beads, tire treads, tire cords, and the tire belts (fabric). Tire beads are coated wires inserted in the pneumatic tire at the point where the tire meets the wheel rim (on which it is mounted) they ensure a seal between the rim and the tire. The tire treads are the part of the tire that meets the road surface their design and composition depend on the use of the tire. Tire cords are woven synthetic fabrics (rayon, nylon, polyester) impregnated with rubber they are the body of the tire and supply it with most of its strength. Tire belts stabilize the tires and prevent the lateral scrubbing or wiping action that causes tread wear. 

Major applications of fibers lie in apparel, home furnishing, and industrial products. In each of these, manufactured fibers have made large inroads, and currently their usage dominates. As an illustration, consider the changes that have taken place in the use of the materials required in the manufacture of tire cords. Originally made from cotton, rayon took a... 

For the purpose of conversion to textile fibers, dispersions or solutions of cellulose or its derivatives are achieved by various means, in order to make possible the extrusion of the fiber-forming material through the small orifices of the spinning jets. Wood pulps prepared for these and similar uses (such as the manufacture of cellophane) are known as dissolving pulps. The manufacture of dissolving pulps is a highly developed art, with processes protected by patents or, more effectively, within company files. The purification of sulfite pulps to a degree suitable for manufacture of textile rayon (90 to 94% alpha-cellulose), tire cord (94 to 9.5% alpha-cellulose), and cellulose acetate (9.5 to 90% alpha-cellulose) requires some kind of... 

Du Font s major contribution to the country s war effort in World War 1 was the manufacture of explosives. By the time World War 11 erupted, explosives was just one of the many Du Pont products needed in the war effort. The insatiable appetite of the war machine imposed numerous demands on technical personnel to build new process lines (over 50 plants were built) in record time and to develop specialty products by yesterday. Chemical engineers played a key role in meeting these demands. Since natural rubber was no longer available, plants to manufacture synthetic rubber such as neoprene had to be built. Rayon and nylon were used in tire cord. Industries producing combat equipment needed heavy chemicals. The emergence of air power required special chemical materials such as plastic enclosures. 

A tire is a textile-steel-rubber composite the steel and textile cords reinforce the rubber and are the primary load-carrying structures within the tire. Because of the performance demands of fatigue resistance, tensile strength, durability, and resilience, seven principal materials have been found suitable for tire application cotton, rayon, nylon, polyester, steel, fiberglass, and aramid the latter three materials find primary usage in the tire crown or belt region. 

The first synthetic fiber for tires was rayon. Cellulose is initially treated with sodium hydroxide to form an alkali cellulose. It is then shredded and allowed to age in air, where it is oxidized and undergoes molecular weight reduction to enable subsequent spinning operations. Treatment with carbon disulfide produces cellulose xanthate, which is then dissolved in sodium hydroxide to form viscose. The material undergoes further hydrolysis and is then fed into spinnerets to produce the fiber. This fiber is passed through a bath of sulfuric acid and sodium sulfate, where the viscose fibers are further coagulated. 

Cellulose, which is found in plant walls, is the most abundant raw material on Earth. Millions of pounds of this biorenewable polymer are produced every year. The total worldwide consumption of cellulosic fibers in 1998 was 4817 million pounds [1]. Cellulose is plentiful, inexpensive, and biodegradable. It is capable of producing a number of fibrous products with excellent properties whose utility extends into numerous end uses and industries. Cellulose is an excellent source of textile fibers, for both the commodity and the high-end, fashion-oriented markets. A common example is rayon. In addition, cellulose provides fibers for industrial end uses requiring strong, tough fibers. A common example is fibers used in tire cord. 

In principle, all the fiber ty pes described above can be used advantageously for reinforcing thermoplastic matrix materials to improve their mechanical and thermomechanical properties. This has been demonstrated for PP as matrix material [7]. In what follows, however, the focus is put on rayon tire cord yam, as it has favorable properties (cf. Table 18.1) and is commercially available as a technical (endless) filament yam with suitable yam titre. 

Moisture regain n. The loss of weight on drying, expressed as percent of dry weight, of a pre-dried material exposed for a specified time to a specified humidity and temperature, then over-dried at a temperature above 100°C. ASTM D 885 (Section 07.01) describes a procedure recommended for rayon yarns and tire cords. 

Tire cord n. A textile material used to impart the flex resistance necessary for tire reinforcement. Tire yarns of polyester, rayon, nylon, aramid, glass, or steel are twisted to 5-12 turns/in. Two or more of these twisted yarns are twisted together in the opposite direction to obtain a cabled tire cord. The twist level required depends on the material, the yarn linear density, and the particular application of the cord. Normally, tire cords are twisted to about the same degree in the S and Z directions, which mean that the net effect is almost zero twist in the finished cord. 

In the 1940s rayon was used almost exclusively in tires. It was difficult to adhere rayon to rubber mechanically because of the smooth surface of the rayon filaments. Fortunately, two Dupont Co. chemists, W. H. Charch and D. B. Maney found that incorporating a resorcinol-formaldehyde thermosetting resin into a rubber latex made a cord adhesive which gave excellent adhesion of rayon to rubber carcass compounds. The same RFL cord adhesive was also used when nylon was introduced as a tire reinforcing material in 1947 and when glass fiber was introduced as belt material in belted bias and radial tires. 

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