Tire cords characterization

Nylon, an aUphatic polyamide, was introduced as a commercial tire cord in 1947 and grew in usage to - 5.4 billion kg/yr (- 2 billion Ib/yr) in the 1990s (10,11). Nylon-reinforced tires use nylon-6 poljmier (polycaprolactam) fibers as well as nylon-6,6 (poly(hexamethylenediainine adipamide)) fibers. Nylon tire cords are characterized by extremely good fatigue resistance in compression and good adhesion to most mbber compounds with simple RFL adhesives. 

Tire cords are characterized for their physical, adhesion, and fatigue properties for use in tires. These characterizations are conducted under normal and varying test conditions to predict their performance during tire operation. Various test methods used to characterize tire cords are described. 

Standard Test Methods for Tire Yarns, Cords, and Woven Fabrics. ASTM standard D885M-94 includes test methods for characterizing tire cord twist, break strength, elongation at break, modulus, tenacity, work-to-break, toughness, stiffness, growth, and dip pickup for industrial filament yams made from organic base fibers, cords twisted from such yams, and fabrics woven from these cords that are produced specifically for use in the manufacture of pneumatic tires. These test methods apply to nylon, polyester, rayon, and aramid yams, tire cords, and woven fabrics. 

This study was undertaken to see if improved tire cord adhesive systems could be developed using poly (DHA-co-4VP) and/or poly(DHA-co-NVP) materials. Since these copolymer systems were new and since previously published Q and e values for DHA (8), 4VP (9), and NVP (10) suggested poor copolymerizability between the monomer sets, a detailed copolymerization study of these monomer pairs was needed. In summary, this study was initiated to determine copolymerization characteristics, i.e. reactivity ratios, of DHA-co-4VP and DHA-co-NVP, to characterize briefly some of the physical and chemical properties of the resultant materials, and to evaluate select copolymers in tire cord adhesive systems. 

When a viscoelastic material such as tire cord or rubber Is subjected to a small amplitude sinusoidal straining, the resulting stress-strain curve Is an ellipse and the material properties are characterized by the real and Imaginary moduli E and E" or the ratio E /E ( tan[Pg.372]

When the strain amplitude Is relatively large as In the case of tire cord In a running tire, the viscoelastic behavior Is no longer linear. The stress-strain loop Is not elliptic but distorted (Figure 1). The material properties In the nonlinear regime can not be represented with the real and Imaginary moduli. In the present study, we characterize the viscoelastic properties In nonlinear regime by the effective dynamic modulus and mechanical loss.(J )... 

Definition Generic name for class of highly aromatic polyamide fibers which are characterized by flame retardant properties Uses Flame retardant protective clothing for military pilots, firefighters, etc. dust-filter bags tire cord bullet-resistant structures business machine components belts hoses ... 

It is important to characterize because it is possible to use PET with relatively low molar mass obtained by solution polycondensation to make fibers or films. For the manufacture of bottles and tire cords, PET obtained by solid-state polymerization possessing a higher molar mass must be used. 

Thermomechanical analysis in the tension mode can be employed in the production of films and fibers to follow the consistency of the product during manufacturing, and to characterize properties of the product, such as CLTE, thermal shrinkage and shrinkage force, and physical properties like Tg and T. All these properties are important, and they determine the end-use possibilities. For example, matching fiber-matrix expansion properties is necessary to avoid delamination of components, such as in tire cords. Shrinkage (i.e., irreversible contraction) is important to avoid in textiles for safe ironing, and it is also an important property in heat-shrink films (Jaffe et al. 1997). 

All adhesives are polymers, and they are used in many ways, for example in composites, automotive tire cords, ply yood, tapes and labels. A particularly demanding application is the cementing of metal joints in military aircraft with polymers such as epoxy resins. The interfaces in such materials must be characterized to determine the strength of the adhesive bond and the relation of such properties as peel strength with... 

ASTM 1070 characterizes steel tire cord and tire bead wire. These materials are considered high carbon steei. Steei beits have carbon content between 0.67 and 0.73% whiie bead wire has a minimum of 0.60% carbon. Also, tire steel belts and tire bead wire possess between 0.40 to 0.70% manganese. 

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