Tire compound

We now turn to complex commercial compounds and consider the interaction between the components. 

---

Reinforcing Fillers. Carbon black is by far the most heavily used reinforcing filler for tire compounds. Annual tire usage of all grades of carbon black is estimated to be over three million metric tons aimuaHy. 

Other Reinforcement Ma.teria.Is. Other materials that have been used in tire compounds for reinforcement are chopped wire (brass-coated), cotton and nylon flock, chopped nylon strands, polyethylene, zinc oxide, and chopped Kevlar. Most of these materials have very limited apphcation and some are obsolete. Others are used more extensively in soHd mbber industrial tires than in pneumatics. 

The petroleum oils are of three basic types aromatic, naphthemic, and paraffinic. Aromatic oils contain hazardous materials that require special handling precautions. Naphthenic oil does not contain hazardous levels of polynuclear aromatics (PNAs) and is less hysteretic. Because of these considerations the naphthenic oil is gaining in usage at the expense of more utilized aromatics. Paraffinic oil is only used modestly in tire compounds. The... 

Tire compounders generally use two basic approaches to formulate for achieving desired tire performance the use of known relationships of a given compound to a specific performance parameter, and estabUshing the relationships of physical properties to a given performance parameter. 

Wire cords are particularly subject to degradation of their adhesion values by moisture. To combat this, halogenated butyl (HIIR) is used in tire innerliners because of its property of low air and water vapor diffusion rates. Moisture is present in most air pumps and many tires are mounted with water left in the tire on mounting. For these reasons tires and tire compounds are tested extensively at simulated aging conditions in the laboratory and on test vehicles before they are sold to the customer. 

Dibenzjiamine, [103-49-17, CgH CH2NHCH2CgH (bp, 300°C at 101.3 kPa) is produced by reaction of benzyl amine with benzaldehyde and hydrogenation of the Schiffs base. It is used in mbber and tire compounding, as a corrosion inhibitor, and as an intermediate in the production of mbber compounds and pharmaceutical products. 

The chemical potential diagram for this ternaty system (Figure 3.3) shows that the reaction with the elements would reduce the iodine pressure to a very low value, which is not suitable for CVD, whereas tire compound Ta5Si3, in which the chemical potentials of the two elements are about 40kJgram-atom would be suitable for CVD at about 1300 K. 

We do not discuss in detail the cases of tautomerism of heterocycles embedded in supramolecular structures, such as crown ethers, cryptands, and heterophanes, because such tautomerism is similar in most aspects to that displayed by the analogous monocyclic heterocycles. We concentrate here on modifications that can be induced by the macrocyclic cavity. Tire so-called proton-ionizable crown ethers have been discussed in several comprehensive reviews by Bradshaw et al. [90H665 96CSC(1)35 97ACR338, 97JIP221J. Tire compounds considered include tautomerizable compounds such as 4(5)-substituted imidazoles 1///4//-1,2,4-triazoles 3-hydroxy-pyridines and 4-pyridones. 

The friction coefficient is defined as the tangential force acting on a sliding body to the ground reaction force. For rubbers this is a function of the ground pressure. Its dependence has been discussed sufficiently in the literature where it was shown that this is important for soft rubbers on smooth surfaces [2,3], but is of little influence for tire compounds on roads which are always sufficiently rough for the load dependence to be small if not completely absent [4,5]. 

FIGURE 26.62 Abrasion of OESBR and an 80 natural rubber (NR)/20 butadiene rubber (BR) blend tire compound as function of slip angle at a load of 76 N and a speed of 19.2 km/h. 

FIGURE 26.70 Correlation coefficient between road test ratings of three truck tire compounds on re-treaded tires at two different axles and laboratory ratings as function of log energy and log speed. 

FIGURE 26.71 Correlation and regression coefficients between road test ratings of seven truck tire compounds 80 SBR/20 NR differing by type and amount of filler and laboratory abrasion ratings obtained on LAT 100 testing equipment. 

FIGURE 29.6 Temperature profile of the phase angle tan 8 for a 75 phr N234 carbon black-filled versus a 75 phr silica/silane-reinforced green-tire compound. (From Wang, M.-J., Rubber Chem. Technol., 71, 520, 1998.)... 

Isobutylene isoprene rubber (IIR), in tire compounding, 21 807 Isobutyl formate, physical properties, 6 292t... 

Mechanical scales, 26 229-236 functionality of, 26 251 Mechanical seals, for pumps, 21 81 Mechanical strength measurement, in tire compounding, 21 811 Mechanical stress, in piezoelectric materials, 22 709... 

Overall heat-transfer coefficient, 13 244 Overall return rate (ORR), 9 545 Overbasing, 15 423 Overcladding, in optical fiber manufacturing, 11 144 Overcoat layers, in photography, 19 199 Overcuring, in tire compounding, 21 810 Overfeed/underfeed drums, 15 439-440 Overflow... 

Peptizers, in tire compounding, 21 810 Pepto-Bismol, 4 36 Peptone, killing rate of e. coli, 8 64It Peracetic acid, 21 46-47 disinfection via, 8 630 production from acetaldehyde, 1 102, 111 Peracids, 9 369-370, 370-371, 372 10 378, 380... 

Polybutadiene (PB), 9 558 14 246 24 703 commercial block copolymers, 7 648t oxygen permeability at 25°C, 3 400 physical properties of, 4 376t in rubber compounding, 21 764-765 synthesis, 4 375-377 in tire compounding, 21 807 nel-Polybutadiene, 7 610t Polybutadiene-based urethane sealants, 22 36... 

---