Tire adhesion

Bond, R. (1990) Tire adhesion role of elastomer characteristics, in Supplementary Volume 2 of the Encyclopedia of Materials Science and Engineering, ed. Cahn, R.W. (Pergamon Press, Oxford) p. 1338. 

The theory of viscoelastic braking in liquid spreading exposes the various possibilities that may exist for controlling wetting or dewetting speeds by changing solid rather than liquid properties. Applications may exist in the fields of contact lenses, printing, and vehicle tire adhesion. 

Zinc oxide, ZnO, is a white powder (yellow when hot) rnade by burning zinc vapor or by roasting zinc ores. It is used as a pigment (zinc white), as a filler in automobile tires, adhesive tape, and other articles, and as an antiseptic (zinc oxide ointment). 

Styrene-butadiene rubber (SBR) is a random polymer made from butadiene and styrene monomers. It possesses good mechanical property, processing behavior, and can be used like natural rubber. Moreover, some properties such as wear and heat resistance, aging, and curing property are even better than in natural rubber. Styrene-butadiene rubber was the first major synthetic rubber to be produced commercially. Now it has become the most common rubber with the largest production and consumption in the synthetic rubber industry. It can be widely used in tire, adhesive tape, cables, medical instruments, and all kinds of rubberware. 

Finaprene . [FinaChem.] Polybutadiene, styrene-butadiene, styrene iso-prene, or carboxylated styrene butadiene elastomers for footwear, tech, goods, tires, adhesives, bitumen modification, plastic modification. 

Chem. Descrip. Neodecanoic acid CAS 26896-20-8 EINECS/ELINCS 248-093-9 Uses Intermediate used as the acid, its ester (for prod, of syn. lubricants), acid chloride (for prod, of peroxides for polymer prod.), or metal salt deriv. (used in tire adhesives, paint driers, PVC stabilizers, chem. processing catalysts, polyester cure catalysts, wood preservatives, fuel additives) metal extraction agent... 

Tire adhesives, soaps, driers 11.0 Soaps, cointlexes made from metal powder — ... 

Tire adhesives Resorcinol-formalde- hyde Natural rubber ... 

The primer has a polarity intermediate to that of tire adhesive and adherend surface. 

If the silica network reforms quickly and is strong enough, tire adhesive or sealant will not sag during application and cure. The strengtii of the silica network is measured by its yield value, the force required to initiate flow in the adhesive or sealant. The higher the yield value, the greater the thickness of adhesive or sealant that can be applied before sagging occms. 

A large number of studies concerned witli tliiol-tenninated molecules has been directed at tire preparation of tailored organic surfaces, since tlieir importance has been steadily increasing in various applications. Films of o> functionalized alkanetliiols have facilitated fundamental studies of interfacial phenomena, such as adhesion [190, 191], corrosion protection [192], electrochemistry [193], wetting [194], protein adsorjDtion [195, 196] or molecular recognition [197, 198, 199, 200 and 201] to mention only a few. 

Another market appHcation for naphthenic acid is the tire industry, where cobalt naphthenate is used as an adhesion promoter (see Adhesives Tire cords). Cobalt naphthenate improves the bonding of brass-plated steel cords to mbber, presumably by suppressing the de-zincification of brass (50). Its first reported use was in 1970 and the first patent for its use was issued in 1975 (51). About 900 t of cobalt naphthenate is used worldwide as an adhesion promoter, half of it in North America. The unit value fluctuates between 8.75—13.25 /kg because of the volatility of cobalt prices. Although it is the industry standard, the use of cobalt naphthenate is declining with the advent of more economical high metal-containing substitutes. 

Polymers. AH nitro alcohols are sources of formaldehyde for cross-linking in polymers of urea, melamine, phenols, resorcinol, etc (see Amino RESINS AND PLASTICS). Nitrodiols and 2-hydroxymethyl-2-nitro-l,3-propanediol can be used as polyols to form polyester or polyurethane products (see Polyesters Urethane polymers). 2-Methyl-2-nitro-l-propanol is used in tires to promote the adhesion of mbber to tire cord (qv). Nitro alcohols are used as hardening agents in photographic processes, and 2-hydroxymethyl-2-nitro-l,3-propanediol is a cross-linking agent for starch adhesives, polyamides, urea resins, or wool, and in tanning operations (17—25). Wrinkle-resistant fabric with reduced free formaldehyde content is obtained by treatment with... 

Nltropropane. As much as 9100 t of 2-nitropropane once were consumed for use in coatings annually. Concern about toxicity and a general movement to low volatile organic compound (VOC) coatings have resulted in almost the complete disappearance of this use for 2-nitropropane. However, derivatives such as 2-meth5l-2-nitro-l-propanol (used in tire cord adhesive) and 2-amino-2-methyl-l-propanol (a pigment dispersant and buffer), have served as an outlet for 2-nitropropane production. 

In the category of industrial appHcations, nylon is the predominant fiber used in the carcass of bias tmck, racing car, and airplane tires because of its exceUent strength, adhesion to mbber, and fatigue resistance. Nylon is used less in the carcass of radial tires for automobiles and in replacement bias and bias-belted tires because of the development of temporary flat spots. For this reason, nylon has lost most of this market to polyester. 

Some amino resins are used as additives to modify the properties of other materials. For example, a small amount of amino resin added to textile fabric imparts the familiar wash-and-wear quaUties to shirts and dresses. Automobile tires are strengthened by amino resins which improve the adhesion of mbber to tire cord (qv). A racing sailboat may have a better chance to win because the sails of Dacron polyester have been treated with an amino resin (1). Amino resins can improve the strength of paper even when it is wet. Molding compounds based on amino resins are used for parts of electrical devices, botde and jar caps, molded plastic dinnerware, and buttons. 

Tire Cord. Melamine resins are also used to improve the adhesion of mbber to reinforcing cord in tires. Textile cord is normally coated with a latex dip solution composed of a vinylpyridine—styrene—butadiene latex mbber containing resorcinol—formaldehyde resin.. The dip coat is cured prior to use. The dip coat improves the adhesion of the textile cord to mbber. Further improvement in adhesion is provided by adding resorcinol and hexa(methoxymethyl) melamine [3089-11 -0] (HMMM) to the mbber compound which is in contact with the textile cord. The HMMM resin and resorcinol cross-link during mbber vulcanization and cure to form an interpenetrating polymer within the mbber matrix which strengthens or reinforces the mbber and increases adhesion to the textile cord. Brass-coated steel cord is also widely used in tires for reinforcement. Steel belts and bead wire are common apphcations. Again, HMMM resins and resorcinol [108-46-3] are used in the mbber compound which is in contact with the steel cord to reinforce the mbber and increase the adhesion of the mbber to the steel cord. This use of melamine resins is described in the patent Hterature (49). 

Insoluble Sulfur. In natural mbber compounds, insoluble sulfur is used for adhesion to brass-coated wire, a necessary component in steel-belted radial tires. The adhesion of mbber to the brass-plated steel cord during vulcanization improves with high sulfur levels ( 3.5%). Ordinary rhombic sulfur blooms at this dose level. Crystals of sulfur on the surface to be bonded destroy building tack and lead to premature failure of the tire. Rubber mixtures containing insoluble sulfur must be kept cool (<100°C) or the amorphous polymeric form converts to rhombic crystals. 

The apex (often referred to as bead filler) compound must be formulated for excellent dynamic stiffness to facilitate stress distribution and provide good car handling properties. The bead insulation compound must possess good adhesion to this most important component for enclosing the pHes of the tire and holding the tine to the rim. The chafer/rim strip compound protects the pHes from rim abrasion and seals the tire to the rim. 

Solubihty parameters of materials are important in processing of compounds /components. A material used in excess of this parameter can bloom (move to the surface of the component) and render it difficult in final tire assembly or block desired migration and weaken component interfaced adhesion. 

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