Rubber consumption

Table 4. Worldwide Long-Term New Rubber Consumption by Elastomer Type, 10 t...

Table 4. Worldwide EPM and EPDM Consumption as Percentage of Total Rubber Consumption ...

Synthetic rubber consumption, 9 556t Synthetic sequences, microwaves in, 16 549-552... 

The balance between natural rubber and SBR is a delicate one. Natural rubber has made a comeback and reversed its downward trend. Developments of rubber farming have raised the yield from 500 Ib/acre/yr to 2,000-3,000. Petrochemical shortages and price increases have hurt SBR. Finally, the trend toward radial-ply tires, which contain a higher proportion of natural rubber, favors this comeback. Fig 18.1 shows the U.S. natural rubber consumption trends vs. U.S. SBR production, where this bounceback of the natural rubber market is very evident from 1980 to the present. The competitive price structure for these two elastomers through the years has been very evident, and their prices are never too far apart. 

If one considers that the automobile sector accounts for 75 percent of rubber consumption in developed countries, it stands to reason that the longlife radial frame and smaller diameter tires of modem vehicles should require smaller amounts of rubber for the same number of cars produced in the United States alone, rubber consumption has fallen from 3.2 million tons in 1977 to a little over 2.6 million tons in 1989. This implies a consumption of some 150,000 tons of organic additives. 

TABLE 16.2 Worldwide Rubber Consumption Forecast, 2008 (Metric Tons)... 

The 2003 synthetic rubber capacity by type is presented in Table 16.1, and Table 16.2 lists the worldwide rubber consumption forecast by type for 2008. 

Natural rubber accounts for about 25% of total rubber consumption. It is produced from the Hevea brasiliensis tree, being formed by isoprene units with cis-1,4 links. Natural rubber is used in tyres and for retreading, latex, mechanical goods, etc. 

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]. 

Composition. Chlorinated rubber combination paints contain a second resin as the property-determining binder. The chlorinated rubber is added to an alkyd resin, acrylic resin, or bituminous substances to improve properties such as drying rate, water resistance, or chemical resistance. This application only accounts for a small proportion of the total chlorinated rubber consumption. 

Rubber consumption is dominated by tyre production. In these, conveyor belts, and pressure hoses, thin layers of either steel wire or polymeric fibre reinforcement take the main mechanical loads. These layers, with rubber interlayers, allow flexibility in bending, whereas the reinforcement limits the in-plane stretching of the product. The applications are dominated by natural rubber and styrene butadiene copolymer rubber (SBR). Other rubbers have specialised properties butyl rubbers have low air permeability, nitrile rubbers have good oil resistance, while silicone rubbers have high and low temperature resistance. Rubbers play a relatively small role in this book, but the rubbery behaviour of the amorphous phase in semi-crystalline thermoplastics is important. 

World rubber usage of around 25.8 million metric tons is split between natural rubber, which constitutes about 43% of global consumption, and synthetic rubber, of which styrene-butadiene rubber (SBR) accounts for 21%. The balance of synthetic rubbers (36%) consists of polybutadiene rubber (BR) and a range of specialty polymers such as polyurethanes, halogenated polymers, silicones, and acrylates. Traditionally, the growth of synthetic and natural rubber consumption is virtually in line with the change in gross domestic product of, collectively. North America, Europe, Japan, China, and India. 

Global natural rubber consumption is split among tires (75%), automotive mechanical products (5%), nonautomotive mechanical products (10%), and miscellaneous applications such as medical and health-related products (10%). Since the 1960s, the quality and consistency of natural rubber has improved, primarily because of the implementation of standard specifications defining a range of grades of rubber. Natural rubber is available in three basic types technically specified rubbers, visually inspected rubbers, and specialty rubbers. 

Both NR and SR are traded in a dry and in a liquid form. The elastomer market (Table 9.5.1) is divided into three major zones (USA, Europe and Southeast Asia) each of which has its own dynamics very closely linked to its internal growth. In the years 2006-2007 China increased its synthetic rubber consumption (-1-19.3%) more quickly than its natural rubber consumption... 

Fig. 1. World-wide rubber consumption according to grade (total market in 1997 16.6 million t/a) [1].

Depending on origin, a distinction is made between natural and synthetic rubbers. Malaya, Indonesia, Thailand, Ceylon, Vietnam, and Liberia are important natural rubber producers. About two thirds of rubber consumption is provided by synthetic rubbers (Table 37-1), of which styrene-butadiene rubber is produced in the largest quantities. 

The diene rubbers described in Section 37.2 represent about 98% of total rubber consumption. The remaining 2% is made up of a whole series of what are known as speciality rubbers with the most varied monomeric units ... 

During 2001, the world s natural rubber consumption was 7.07 million metric tons and 75% of it was... 

The most important rubber application is in tyre compounds, about 70% of the worldwide natural and synthetic rubber consumption. A conventional tyre for passenger cars contain more than ten different rubber compounds, developed as a function of the specific requirements of the various tyre parts and thus based on optimized combinations of rubbers and other ingredients. 

This chapter is a perspective of the science and technology of elastomers and does not include a market analysis. Nevertheless, we must mention that the global market for these materials is large (Fig. 4.1). Global vulcanizable (conventional, vulcanizable) rubber consumption was about 20 million metric tons in 2004, whereas thermoplastic elastomer (TPE) consumption was about 1.5 million metric tons. The consumption of conventional rubbers is growing at a rate of about 3 to 4 percent, whereas the growth of TPE consumption is growing at about twice that rate. 

Tires are the largest consumer of synthetic rubber. Automotive components and tires together account for nearly 70% of synthetic rubber consumption. Additional consumption is found in miscellaneous mechanical goods, plastic composites, and construction applications such as roofing, vire and cable covers, and adhesives. For SBR specifically, passenger tire production consumes approximately 50%, truck tires and tire retreading a further 20%, and the balance is in specialty tires, automotive and non-automotive components. Polybutadiene consumption is similar to SBR with tires accounting for nearly 75% of total polymer production. 

Sinopec, China s state-owned petrochemical and polymer company, is increasing synthetic rubber capacity across the board, including butyls, SBRs, nitrile, and chloroprene. Sinopec is starting polyiso-prene and EPR production, although the company did not produce polyisoprene or EPR prior to 1999. Total synthetic rubber capacity will be 1.15 million metric tons/y by 2000. China s synthetic rubber consumption is forecast by the company to be almost 7 million metric tons/y in 2000. ... 

Expressed as percentages of total annual synthetic rubber consumption worldwide, EPM and EPDM have increased from 0% in 1964 to 8.9% in 2000, as shown in Table 4. EPM and EPDM still show a steady growth over the years. 

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