Synthetic man-made rubber can be produced through a chemical process, but people have not been able to produce a synthetic rubber that has all the properties of natural rubber.
So, natural rubber cannot be replaced by synthetic rubber in most of its applications. This is why natural rubber is still very important to human society [ 2 ]. As far back as B. It was not until the conquest of America that the use of rubber reached the western World. Christopher Columbus was responsible for finding rubber in the early s. Natives from Haiti played football with a ball made of rubber, and later, in , Fray Juan de Torquemada wrote about indigenous and Spanish settlers of South America wearing shoes, clothing and hats made by dipping cloth into latex, making these items stronger and waterproof.
But rubber had some problems: it became sticky in response to warm weather and it hardened and cracked with cold weather. There, he found two different trees containing latex: Hevea brasiliensis Figure 1B and Castilla elastica [ 3 ], but only the first became important as a natural rubber source.
The reason why the Hevea tree succeeded over the Castilla tree was the way its latex was transported along the trunk. The Hevea tree has connected latex tubes Figure 1A that form a network, whereas the Castilla tree does not form a connected system. Thanks to its connected system, the Hevea tree bleeds latex when a special incision is made in its trunk Figure 2.
Without the latex tube connections, the Castilla tree does not bleed latex, making harvest of rubber more difficult. In , Charles Goodyear invented the vulcanization process, solving many of the problems associated with rubber. Vulcanization is the process of treating rubber with sulfur and heat, to harden it while keeping its elasticity. It prevents rubber from melting in the summer and cracking in the winter.
A few years after this important discovery, in , Dunlop invented the air-filled rubber tire, making rubber an extremely important raw material worldwide. Rubber became an essential material for the Industrial Revolution. From to , businessmen were pushing entrepreneurs and traders to increase the amount of rubber extracted from Amazonian trees. During this period, the Brazilian Amazon was the only source of rubber and they controlled the price, making rubber expensive. At the same time, as more and more industry was developing in Europe and USA, more uses for rubber were being found [ 4 ].
Rubber was such an important material for Brazilians that they prohibited the export of rubber seeds or seedlings. However, in , H. Wickham managed to smuggle 70, rubber seeds, hidden in banana leaves, and brought them to England.
From those seeds, only 1, seedlings survived and were sent to Malaysia to start the first rubber plantations in Asia. While working there, he found the first 11 rubber trees that were planted in Malaysia and he started promoting the establishment of rubber tree plantations. How is rubber made? The raw materials to make rubber can be natural or synthetic. Natural Rubber Natural rubber is made from liquid tree sap, latex, that comes from a variety of trees and plants.
Synthetic rubber Synthetic rubber is made by linking polymer molecules together. Processing rubber Both natural and synthetic rubber are processed to turn it into a usable product. Synthetic rubbers are available in many forms, thanks to the wide range of applications from the industrial market.
A few examples include styrene-butadiene rubber, polybutadiene rubber, and polyisoprene rubber. Since synthetic rubber is used in vastly different ways, its properties vary from form to form. But in general, there are a few distinct differences between natural and synthetic rubber that are important to note.
Natural rubber is resistant to wear from chipping and tearing thanks to its high tensile strength. Damages from heat, light, and ozone exposure, however, are more likely. Its tacky properties, especially toward steel cords, make it common in vehicle tires. Synthetic rubber is more resistant to abrasion than natural rubber. Its grease and oil resistance also makes it a popular choice for corrosive environments.
Synthetic rubber also has a strong resistance to heat and time—many varieties of synthetic rubber are even flame-resistant. This makes it a common choice for electric insulation. Synthetic rubber is also flexible, even in relatively low temperatures. Synthetic rubber is more commonly used today because of its availability and ease of production, and in special circumstances that require its resistance to extreme temperatures and corrosion.
To test the properties of your natural or synthetic rubber in a multitude of environments and situations, contact ACE Products and Consulting. There are countless other applications for different synthetic rubbers, ranging from chewing gum to sporting goods to belts and moldings.
Natural rubber is commonly used to produce high-performance vehicle tires that will need excellent tear strength, even at high temperatures caused by friction. Aircraft tires, heavy truck tires, and even sophisticated race car tires are often made from natural rubber.
Silicone rubber, like rubber, is an elastomer. A monomer is used to bind molecules together to create polymers. The chemicals will be bonded together by monomers to create polymers. Rubber substances will then undergo vulcanisation to process them into rubber products.
Vulcanisation is the process in which polymers are converted into a more durable material by adding sulphur or other accelerators. Synthetic rubber is commonly used to produce products like rubber matting, rubber gaskets, door mats and more.
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