Why natural rubber is rarely used in heavy tires
Why NATURAL rubber is rarely used in heavy tires Heavy tires are purchased mainly for their durability and re-coating capability, which is derived from the natural rubber properties used in them. The re-coating capability in the lightweight tire market is not that important. In the formulation of the compound used in aircraft tires, natural rubber is usually used because of its resistance to the heat generated during landing and take-off of the aircraft. On the other hand, in agricultural tires, because they are often used in soft and muddy soils, the formulation used is programmed based on less heat. Therefore, natural rubber is rarely used in their construction. In the formulation of these tires, mainly oiled synthetic rubber (SBR) is used. For various reasons, polybutadiene synthetic rubber alone is not very important, but its combination with two other types of rubber improves abrasion resistance and prevents high heat in service…
What is global trade?
Global trade The simplest definition is international trade, which means the process of trading goods and products between two or more foreign markets. International trade allows countries to expand their markets and gain access to goods and services that might never be available in that country without international trade. As a result of international trade, markets become more competitive, which ultimately leads to more competitive pricing and cheaper goods for the consumer. International trade and foreign trade have been a fundamental factor in the emergence of the global economy. In international trade, supply and demand, and ultimately prices, are affected by global events, as a result of which global economic variables are defined and examined globally. For example, political change in Asia could lead to higher labor costs. This can increase the cost of producing an agricultural product, and increase the price of a product that a European consumer may…
Structure and Properties of Styrene butadiene rubber
While most of the properties of SBR are comparable with NR, but in some respects like heat build-up, tack and gum tensile strength make it inferior to natural rubber. Other disadvantages include: Low elongation at break Low hot tear strength Hysteresis, resilience But the addition of resins and reinforcing fillers adequately improve these properties. However, there are properties which makes it superior over natural rubber. These include: Better process ability, Slightly Better heat aging Better abrasion resistance and resistance to degradation (under heat) Also, scorch problems are less likely to occur with SBR than with NR. Overall, the most important factors in the commercial viability of SBR making it material of choice over other rubbers are: Wide availability Low cost compared with those of all other synthetic rubbers, Ability to accept high filler levels, Relatively stable price compared with that of NR and Overall properties on a cost/performance basis Rubber…
Styrene butadiene rubber categories in terms of production and polymerization methods
Emulsion method In this method, polymerization is done through free radicals, which is done in both hot and cold states. The product obtained by cold method in the presence of oil or in the presence of oil-soot has high linearity, narrow molecular distribution, high molecular mass and difficult processing. The product obtained by hot method is also highly branched and has a wide molecular mass distribution, good process ability and higher percentages of 1 and 2-vinyl. Solution method In this method is ion polymerization, the product of this method has high linearity, high flexibility and high abrasion and tear resistance against dynamic stresses. Gel method The product of this method has a weak percentage of chemical bonds during the polymerization reaction between the chains, which reduces the mobility of the chains and improves processability. cooking methods It is mainly done by sulfur vulcanization method. The cooking speed in the SBR…