Tread rubber composition

Polysiloxane added to tire tread rubber composition improves processing characteristics of rubber containing silica but also improves several characteristics of tire such as temperature dependency of hardness, grip on ice/snow, abrasion resistance, etc. Polysiloxane does not migrate from tire composition. ... 

Oshima, K. Tire tread rubber composition containing nitrogen-containing cychc compound. Jpn. Kokai Tokkyo Koho JP 2002097310, 2002 Chem. Abstr. 2002,136, 280640. 

Amine or amide modification involves coupling the anionic polymer chains with a tertiary amine to obtain tread rubber compositions that meet tyre requirements for wet skid, rolling and wear resistance. Heat emission and wear resistance can be further improved by quaternizing the tertiary amino groups. 

Black filled tread rubber compositions contained 100 phr polymer ... 

DEVELOPMENT OF TIRE TREAD RUBBER COMPOSITION WITH COMBINATION OF LOW ROLLING RESISTANCE AND HIGH WET TRACTION... 

Tire shredding, mechanical, 21 470-472 nylon, 19 765-766 reclaimed rubber in, 21 784-785 Tire-to-energy facilities, 21 466 Tire tread compounds, composition of, 21 806t... 

The resins in the friction dust area tend to be rigid and the flexibility and plasticity associated with the long alkyl chain of phenolic lipids have been used in natural rubber vulcanisation by for example incorporating crosslinking with phosphorylated cardanol (ref. 252). Unpolymerised CNSL phenols have been used in natural or diene rubber compositions for tyre treads to give an improved dynamic elastic modulus but with the same hardness as formulations without the phenolic addition (ref. 253). 

A tire is essentially a cord-rubber composite. Tires have plies of reinforcing cords extending transversely from bead to bead, on top of which is a belt located below the tread. The belt cords have low extensibility and are made of steel and fabric depending on the tire application. The belt cords are at a relatively low angle, between 12° and 25°, and serve as restrictions to the 90° casing pUes. 

Elastomers Car tires (tread) Rubber tubing Membranes, rubber-metal composites... 

EP0810258, E. Custodero, and J.-C.Tardivat, Diene rubber composition containing alumina as reinforcing filler and use in tire treads (1996). 

February 17,1998 Silica Reinforced Rubber Composition to Goodyear Tire Rubber, U.S. Patent 5,719,208, February 17, 1998 and Silica Reinforced Rubber Composition and Tire With Tread to Goodyear Tire Rubber, U.S. Patent 5,719,207, February 17, 1998. 

Modeling is the method of choice for analyzing passenger car cord-reinforced rubber composite behavior. Large scale three-dimensional finite element analysis (FEIA) improves imderstanding of tire performance, including tire and tread behavior when the rubber meets the road. ... 

Dry RubbGr. Because of its enhanced crystallizability, guayule rubber can exhibit superior failure properties in unfilled rubber compositions. As a double network, an elastomer cured a second time while in a deformed state guayule rubber exhibits substantially better fatigue resistance than deproteinized Hevea rubber (118). When compounded with carbon black, guayule rubber and Hevea rubber behave similarly (119). In tread and wire skim stocks, the compoimding and performance behavior of guayule rubber was comparable to that of Hevea rubber (Tables 7, 8) (120). 

The sort of droplet-like structure developed by Novamont (Figure 8.5) is easily dispersible in rubbers and allows a decrease of hysteresis in the final rubber compositions, which is useful for low rolling resistance treads in tyres. The first industrial application in this field was made by Goodyear in 2001, when the Biotread GT3 tyre was launched in Europe [132-136]. 

Guided by the above studies, we have developed a number of experimental rubbers, and blends of rubbers, for application in tire treads. The experimental rubbers consist of vinyl BR s, SBR s, and high trans SBR s prepared by the anionic polymerization techniques, previously described in this paper. Tan 6 and Tg results for some of these rubber compositions are plotted in Figure 19. Also shown are the corresponding results for rubber compositions based on conventional rubbers used in the past. These data show that the experimental compositions have significantly lower lYO tan 6, and have simultaneously higher glass transition temperatures, when compared to compositions based on conventional rubbers. 

We have made tire treads with some of the rubber compositions that were used for the study of tan 5 and Tg, shown in Figure 19, The test results on coefficient of wet skid resistance of tread rubbers and rolling... 

Otoyama, T Mori, N. Polyrotaxane-containing rubber compositions with good workability, and pneumatic tires with good driving stability and durability having their treads. Jpn. Kokai Tokkyo Koho JP 2009062485, 2009. 

There is one obvious drawback of high-hysteresis rubber. In normal rolling operation, considerable elastic deformations still take place in the tyre wall, and high-loss tyres will consume fuel and generate considerable heat. The way out is to use a low-loss tyre covered with a high-loss tread - another example of design using composite materials (Fig. 26.9). 

The pneumatic tire has the geometry of a thin-wallcd toroidal shell. It consists of as many as fifty different materials, including natural rubber and a variety ot synthetic elastomers, plus carbon black of various types, tire cord, bead wire, and many chemical compounding ingredients, such as sulfur and zinc oxide. These constituent materials are combined in different proportions to form the key components of the composite tire structure. The compliant tread of a passenger car tire, for example, provides road grip the sidewall protects the internal cords from curb abrasion in turn, the cords, prestressed by inflation pressure, reinforce the rubber matrix and carry the majority of applied loads finally, the two circumferential bundles of bead wire anchor the pressnrized torus securely to the rim of the wheel. 

Standardisation of EPDM characterisation tests (molecular composition, stabiliser and oil content) for QC and specification purposes was reported [64,65]. Infrared spectroscopy (rather than HPLC or photometry) is recommended for the determination of the stabiliser content (hindered phenol type) of EP(D)M [65]. Determination of the oil content of oil-extended EPDM is best carried out by Soxhlet extraction using MEK as a solvent [66], A round robin test was reported that evaluated the various techniques currently used in the investigation of unknown rubber compounds (passenger tyre tread stock formulations) [67]. 

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. 

Butadiene can form three repeat units as described in structure 5.47 1,2 cw-1,4 and trans-, A. Commercial polybutadiene is mainly composed of, A-cis isomer and known as butadiene rubber (BR). In general, butadiene is polymerized using stereoregulating catalysts. The composition of the resulting polybutadiene is quite dependent on the nature of the catalyst such that almost total trans-, A, cis-, A, or 1,2 units can be formed as well as almost any combination of these units. The most important single application of polybutadiene polymers is its use in automotive tires where over 10 t are used yearly in the U.S. manufacture of automobile tires. BR is usually blended with NR or SBR to improve tire tread performance, particularly wear resistance. 

Figure 2.75 shows the constructions of a standard bias (diagonal) ply tire and a radial ply tire. The major components of a tire are bead, carcass, sidewall, and tread. In terms of material composition, a tire on an average contains nearly 50% of its weight in actual rubber for oil extended rubbers (typically containing 25 parts of aromatic or cycloparafiBnic oils to 75 parts of rubber), it is less. The remainder included carbon black, textile cord, and other compounding ingredients plus the beads. 

In essence, a tire is a composite of complex elastomer formulations, fibers, textiles, and steel cord. The term tire structure defines the number, location, and dimensions of the various components used in a tire s composition. The primary components that govern the performance of a tire are the casing plies, bead construction, belts, sidewall, inner liner, and tread. Chafers, flippers, and overlays, which are strips of rubberized fabric located in the bead and crown area of the tire, are termed secondary components because they protect the primary components by minimizing stress concentrations (Ford and Charles, 1988 Davison, 1969). 

The tire is a complicated composite product consisting of tread, undertread, carcass, innerliner, bead, and sidewall. Many different types of rubber and carbon black reinforcement are used in manufacturing tires. Therefore, GRT is a blend of various rubbers and carbon blacks. Accordingly, in using GRT powder and devulcanized GRT in new tire manufacturing, many factors should be considered. Evidently, scrap tire powder can be used as a filler for virgin rubbers and devulcanized GRT can be used in blends with virgin rubbers. This market consumed approximately 1.354 x 10 tons of scrap tire rabber in 2009 (US Scrap Tire Markets, 2009). 

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