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Understanding What Is The Vulcanization Of Rubber

Let’s learn about vulcanization and the process of vulcanization of rubber.

The history of vulcanized rubber stretches back thousands of years, from ancient Mesoamerican civilisations to modern tyre manufacturing. During its development, luminaries like Charles Goodyear and Charles Macintosh played a crucial role. In this section, Martin’s Rubber provides you with interesting facts about the discovery, production, and uses of vulcanized rubber.

What Is vulcanization?

Vulcanization is a chemical process by which the physical properties of natural or synthetic rubber are improved; the resulting rubber is stronger, more elastic over a wider temperature range, and more resistant to swelling and abrasion. The vulcanization process is based on heating rubber with sulfur.

What Is Vulcanized Rubber?

Curing elastomers is called vulcanisation. A rubberised material boasting excellent rigidity and durability is produced by cross-linking sections of polymer chains using sulfur or other elements (including peroxide and metal oxides).

History of Vulcanized Rubber

Mexico’s first recorded major civilization, the Olmecs, is believed to have combined the boiled sap of the Pará rubber tree (hevea brasiliensis) with vine sap to produce the first primitive form of vulcanized rubber. As a result of the process, they were able to waterproof their clothes and play ritualistic ball games.

To make rubber sheeting, Scottish chemist Charles Macintosh and English inventor Thomas Hancock dissolved natural rubber in benzene and heated it at high temperatures in the 1820s. Due to frequent misspellings, the extra “k” stuck on the Mackintosh waterproof fabric.

In order to make the material more thermally stable, sulfur was later added. Macintosh patented this discovery and named it “vulcanisation” after Vulcan, the Roman god of fire, which is widely credited to Goodyear. In essence, this led to the development of the Mackintosh jacket as well as a number of other useful products.

Benefits of vulcanized rubber

As a result of vulcanization, rubber shrinks without losing its original shape. Vulcanization also hardens rubber, making it less susceptible to deformation – especially compared with non-vulcanised rubber, which will deform more rapidly under stress. Rubber becomes harder and more tensile as a result of this process.

  • Return to the original shape,
  • Low water absorption
  • Resistance to oxidation and abrasion
  • Excellent electric insulator,
  • Resistance toward organic solvents
  • Benefits of vulcanization

Making of Vulcanized Rubber

The process of vulcanizing rubber involves several steps. First, the rubber must be immersed in sulfuric acid and all other additives. Several additives are mixed with sulfur to facilitate vulcanization, although sulfur is the primary ingredient. It may contain both pigments to give color and an accelerator to make the process faster.

As a next step, the rubber is molded into the desired shape. Vulcanized rubber cannot be easily molded. As a result, it is difficult to mold due to its strong and elastic properties. This is why the rubber is molded after being immersed in a sulfur-based solution and added additives.

In an oven-like chamber, rubber is heated after it has been molded. The addition of heat helps vulcanize rubber faster while also improving results. Sulfur alone can vulcanize rubber, but heat speeds up the process. Then rubber gets heated at a temperature of 300 to 400 degrees Fahrenheit. Then after taking it out of the oven, allow it to cool.

How Vulcanization Improves The Property of Rubber

Rubber can be vulcanized by applying chemicals – usually sulfur – to alter its physical properties. Rust, corrosion and mold resistance are among the many desirable properties of rubber in its natural state. But the rubber is very soft and highly elastic, which can restrict its performance in certain applications. In order to overcome this challenge, some manufacturers use vulcanized rubber.

How Does Vulcanization Work?

Typically, sulfur is used to vulcanize materials. Natural rubber, as well as synthetic rubber, are affected by sulfur, the 10th most abundant element in the universe. A pressurized mold is used to heat rubber and sulfur to about 280 degrees to 350 degrees Fahrenheit during the vulcanization process. When combined with heat and chemicals, the rubber retracts and hardens.

Other chemicals used in the process are:-

  • Peroxide
  • Metal oxides
  • Acetoxysilane
  • Urethane

Impacts of Vulcanization On Rubber

During vulcanization, rubber is forced to retract, altering its physical properties. Rubber can also be retracted mechanically. Contrary to vulcanization, rubber retains its original shape after vulcanization. Vulcanized rubber shrinks without losing its shape while retaining its original properties. A rubber block is vulcanized to make it smaller while maintaining its shape and not deforming. While vulcanization alters the rubber’s size and shape, it also protects it against future deformation. Rubber becomes less susceptible to deformation as it shrinks. Rubber that has been vulcanized can still deform when stressed, but it won’t deform as easily as conventional rubber. Moreover, the rubber becomes harder when vulcanized, increasing its tensile strength and reducing the likelihood of physical damage. A vulcanization process is permanent, in contrast to thermoplastic chemical processes. Vulcanized rubber objects or materials cannot be reversed once they have been vulcanized.

Conclusion

In this article, we learned lots of things about vulcanization and rubber. It’s a process of manipulating rubber’s properties and making it something new. Stuff like tires is the creation of this process only. This process changed the world of economy. To learn more about vulcanization stay tuned with us.

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