Tyre manufacture

Elastomers, of which vulcanized natural rubber is the most important example, also undergo dramatic changes in mechanical properties when filled with particulate solids. In part, knowledge of this particular type of system has been developed empirically as the technology of car-tyre manufacture has advanced. 

In pneumatic tyre manufacture, the heavy mbber tube to which is admitted the inflation medium... 

JATMA 2002. Tire Industry of Japan 2002. The Japan Tyre Manufacturers Association Inc. World Wide Web Address www.jatma.or.jp. 

The formation of the steel/synthetic fibre/rubber agglomerates is a by-product of the milling process and in part the tyre manufacturing process. The steel belts used in auto... 

The second theory—winter-diffusion—would seem applicable to the particular case of the adhesion of like surfaces (known also as auto-adhesion ). Certainly it occurs in the welding of plastics, and in instances such as tyre manufacture when unvulcanized rubbers adhere spontaneously. On the other hand, it is unlikely that much inter-diffusion takes place when materials dissimilar chemically are brought together. It is well-known that many plastics are incompatible and if mixed will, over a period of time, tend to separate— forming eventually discrete layers. Behaviour of this kind is precisely the reverse of inter-diffusion. 

Hi. Applications in tyre manufacturing. Two important properties of tyres are the so-called rolling resistance and the wet grip, which both depend on the physical characteristics... 

With respect to the solid residue, the authors observed an increase in the char surface area with both temperature and heating rate, values up to 60 m2/g being obtained. These surface areas are large compared with those of the raw carbon blacks used in tyre manufacture. However, the pyrolysis char contains a higher proportion of ash and has a larger particle size, which make this product an... 

The most commonly used rubber in tyre manufacture is styrene-butadiene copolymer containing about 25 wt% of styrene. The presence of a high concentration of double bonds in the rubber backbone makes the alternative of degrading rubber wastes by treatment in hydrogen atmospheres very attractive. Moreover, because used tyres contain significant amounts of sulfur, hydrogenation also favours the removal of this undesired element as H2S, which allows oils to be produced with lower S content than those derived from tyre pyrolysis. 

Tyres and related products Pneumatic tyre manufacturing dominates the rubber industry in terms of the quantity of raw rubber consumption. About 50-60% of the rubber produced in the world is used for manufacturing tyres and related items. Tyre products include pneumatic tyres and tubes, sohd tyres, t)n e flaps, retread material, and puncture repair Wts (PRKs). NR is the ideal base material for tyres for aircraft, racing cars, heavy duty vehicles such as trucks and buses, off the road vehicles, and tractors. An oil extended form of natural rubber could be used as base material for the manufacture of winter tyres [61]. 

Thermoplastic polymers can easily be melted and moulded into flexible shapes. The rigidity and strength of the product can be improved by cross-linking between the polymer chains. One of the first deliberate cross-linking processes was the vulcanisation of rubber, which is used in car tyre manufacture. The process transforms sticky, soft rubber into a hard, flexible material. 

RESIN TYRE MANUFACTURER ACTION RESIN TYPE MANUFACTURER ACTION... 

On behalf of its member companies as DU of chemicals, ETRMA provides GES as well as sector-specific information for registrants to carry out CSA for substances used within the tyre manufacturing industry. The formulation/industrial use of subject chemicals during the tyre manufacturing process, as well as their professional use and service lifecycle stages when used in tyres (articles), are identified in this document. 

In modern vulcanization processes, NR is generally compounded (either under high or low temperature) with 0.5 to 1 wt% of accelerators, different concentrations of CBs (which act as a filler) (up to 45 wt% for tyre manufacturing), low concentrations of aromatic amines and phenols for antioxidation purposes and 5-8 wt% of sulfur. These types of vuleanized NR are commonly known as NR composites (when the filler dimension is on the microscale) or NR nanocomposites (when the filler dimension is on the nanoscale). NR-based composites or nanocomposites will be discussed in more detail in the following sections. 

Styrene-butadiene rubber (SBR) is mainly used for tyre manufacturing and only a small amount is consumed in adhesives. 

A broad range of monomers with relatively low water solubility have been polymerised by conventional emulsion polymerisation. Acrylics, methacrylics, styrene and vinyl acetate are the most common monomers used in preparing latexes for paints, textile binders, and adhesives. Acrylic, polyester, epoxy and urethane dispersions are used in industrial coatings, where higher strength is required. Butadiene is often copolymerised with styrene in producing synthetic rubber for tyre manufacture. 

Silicones confer anti-stick properties on surfaces. Moulds for rubbers, as in tyre manufacture, or for plastics are usually silicone treated to give easy release. Silicones are also useful surfactants and anti-foam agents. 

Given that tyre failure is not a rare event (a recent example is a particular brand used on a recreational use vehicle - R.UV or US, SUV), some tyre manufacturers will promote the idea that their tyres are less prone to failure. No manufacturer could reasonably be expected to produce a tyre that is certain not to fail. Tyre research and consmner... 

The synthetic rubber industry has never looked back and by the 1960s had overtaken NR in terms of production and usage (Table 4.1). At one stage, it was predicted that SBR could eventually replace NR as an industrial elastomer, in particular in tyre manufacturing. However, that prediction never materialized because NR is still needed to provide the required sturdiness and heat resistance in tyre performance. Radial tyres are typically made up of nearly 50% NR whereas aviation tyres require 100% NR in their formulations. Now NR and synthetic rubber complement each other in many applications, each with its niche properties. In the present drive towards sustainable development, NR is viewed as a renewable raw material and is gradually regaining its dominant role. 

Tyre rubber is developed specifically for tyre manufacturing. It is prepared by coagulating NR latex containing oil with wet crumb rubber in the following proportion 30% latex rubber, 30% unsmoked sheet, 30% field coagulum and 10% plasticizer (oil). 

SSBR is used in tyre manufacture, particularly in the tread compound where it gives a good combination of grip, wear and low rolling resistance. It is also widely used in flooring, sheeting and shoe soles. Some types find application in the manufacture of adhesives... 

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