Skip to content
Related Articles

Related Articles

Improve Article
Save Article
Like Article

Rubber – Definition, Types, Processing, Uses

  • Last Updated : 21 Dec, 2021

A polymer is a substance or material made up of many repeating subunits that make up very big molecules, or macromolecules. Both manufactured and natural polymers play crucial and pervasive roles in everyday life due to their wide range of characteristics. Polymers include everything from common synthetic plastics like polystyrene to biopolymers like DNA and proteins, which are essential for biological structure and function. 

Polymers, both natural and manmade, are made by polymerizing a large number of tiny molecules called monomers. In comparison to small molecule compounds, their huge molecular mass results in unusual physical features such as toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semi-crystalline structures rather than crystals.

Rubber

Rubber is a type of polymer that can stretch and shrink. It’s an elastomer that, after being deformed, may revert to its previous shape. Isoprene polymerisation is used to create it (2 methyl-1,3-butadiene). The bark of a rubber tree is used to make natural rubber. 

Rubber was artificially produced overtime to fulfil its enormous demand, and this ushered in a revolution in the realm of polymers.

Chemical Name and Chemical Formula of Rubber

Isoprene (2-methyl, 13-butadiene) is the monomer of natural rubber. Natural rubber is the polymer of this isoprene, and its chemical name is ‘cis – 1,4 – polyisoprene.’

Types of Rubber

Rubbers are divided into two groups based on their origin: natural rubber and synthetic rubber.

  1. Natural Rubber: It’s a natural polymer derived from a rubber tree’s latex sap. Rubber’s elasticity makes it a popular material. Vulcanized natural rubber is used to make a variety of items. Polyisoprene is the chemical name for natural rubber. Natural rubber’s best feature is that it is biodegradable and renewable because it is extracted from trees. Thousands of items, including surgical gloves, medical gadgets, aircraft and vehicle tyres, mattresses, shoe soles, rubber boots, toys, and more, rely on it as basic material.
  2. Synthetic Rubber: Any artificial elastomer is referred to as synthetic rubber. Synthetic rubber is typically made up of additional polymers of polyene monomers, and laminates including such a layer will be categorised as additional polymers unless the synthetic rubber is disclosed as a polysulfide rubber. An elastomer is a material that has the mechanical property of being able to bend far more elastically under stress than most materials while still returning to its original size without permanent distortion. In many circumstances, synthetic rubber can be used in place of natural rubber, especially where better material qualities are required.

Manufacture of Rubber

Manufacture of Natural Rubber

The latex sap of the rubber tree is used to make natural rubber. The latex is harvested by affixing a container to the rubber tree, which is referred to as tapping.

After that, formic acid is used to coagulate the latex. They become a hard mass as a result of this process. These rubbers are now completely dried, either with a series of rollers or by allowing them to air dry for several days. These natural rubbers are now ready for processing and will be used to make a variety of products.

Manufacture of Synthetic Rubber

Various synthetic rubbers are made using the polymerization process, such as neoprene by addition polymerization, Buna-S, and Buna-N through co-polymerization.

  • Neoprene: Neoprene, commonly known as polychloroprene, is a homopolymer made from chloroprene polymerized by free radicals. It has a strong oil resistance and is used to make conveyor belts, hoses, and gaskets, among other things.

  • Buna-S: Buna – S is formed by the copolymerization of 1,3-butadiene and styrene. It has a high tensile strength and can be used as a natural rubber alternative. It’s utilised to create car tyres, footwear components, cable insulators, and other things.

  • Buna-N: Buna – N is a copolymer made by polymerizing 1,3-butadiene with acrylonitrile in the presence of a peroxide catalyst. Oils, petrol, and some organic solvents won’t harm it. They’re typically utilised to make tank linings, oil seals, and other such things.

Processing of Rubber

After natural or synthetic rubber is made, it is delivered to processor plants to be processed into the final product, which may then be utilised to make a variety of goods. Compounding, mixing, shaping, and vulcanizing are the four processes in the rubber processing process.

  1. Compounding: Rubber is fortified with additives and chemicals to improve its tensile strength and characteristics. Carbon black fillers, for example, are added to rubber to boost its tensile strength and protect it from ultraviolet radiation degradation.
  2. Mixing: Rubber must be well mixed with the additives before use. The temperature is raised for this purpose, and the additives are thoroughly blended.
  3. Shaping: Extrusion, calendering, moulding or coating, and casting are four common methods for shaping rubber items. Extruders force a highly plastic rubber through a series of screw extruders to create rubbers. Calendering follows this phase, which involves passing the rubber through a series of smaller gaps between rollers. This roller-die method combines extrusion and calendering to create a superior result. Coating is the application of a rubber coat or the pushing of rubber into cloth or other materials. Rubber coatings are used to make tyres, waterproof textile tents, raincoats, conveyor belts, and other items. Molds are used to make rubber products such as shoe soles and heels, seals, suction cups, and bottle stops.
  4. Vulcanization: The rubber-processing process is finished with vulcanization. Sulfur cross-connections between rubber polymers are formed during vulcanization. Rubber that has fewer cross-connections between its polymers is softer. The elasticity of the rubber is reduced as the number of cross-connections increases, resulting in harder rubber. Rubber would be sticky when hot and brittle when cold if it wasn’t vulcanised.

Uses of Rubber

  • One of the largest consumers of rubber is the tyre and tube industry. To make natural rubber more durable, it is combined with synthetic rubber over time.
  • Rubber is also employed in other areas of the vehicle industry. Seals and various types of cushioning for various car parts are made from natural rubber. For example, it’s used to make brake pads and window and windshield seals in automobiles.
  • Rubber is used to produce airbags in automobiles, which protect passengers from damage caused by accidents.
  • Clothing: Because natural rubber is elastic in its fibrous form, it is utilised to make clothing that is tight-fitting and expandable, such as swimwear and cycling shorts.
  • Rubber is utilised to make flooring in a variety of business establishments, kitchens, and even playgrounds. It creates a cushioned surface that is also slip-resistant and waterproof. It’s simple to keep up with and lasts a long time.
  • Gaskets: Gaskets are used to prevent leakage or fill uneven spaces between two or more mechanical parts.
  • Erasers: This rubber device could “rub” away pencil marks on paper, earning it the name “eraser.”
  • Natural rubber was used by ancient Mesoamerican civilizations to build waterproof shoes and bottles. Not only that, but it was also utilised to make a sports ball for a game called football, which is comparable to modern-day basketball.
  • Rubber is utilised as an adhesive and a protective layer for a variety of surfaces in its latex state.
  • Rubber gloves are a well-known rubber product since they are frequently used to keep our hands safe and clean.
  • Rubber is used to make soundproofing materials and a variety of children’s rubber toys.

Sample Questions

Question 1: What are the elements of rubber?

Answer:

Carbon and hydrogen are the two most frequent components found in rubber. Isoprene (2-methyl-1,3-butadiene), a conjugated diene hydrocarbon, is the monomer of natural rubber.

Question 2: What are the types of rubber?

Answer:

There are two types of rubber: natural and synthetic. Synthetic rubbers are artificial elastomers that are synthesised from petroleum products. Natural rubber is extracted from the latex of the rubber plant, while synthetic rubbers are artificial elastomers that are manufactured from petroleum products. They are twice as strong as natural rubber in terms of tensile strength. They are predominantly 1,3-butadiene derivatives.

Question 3: Why are rubbers called elastomers?

Answer:

An elastomer is a type of polymer that exhibits elasticity. Natural rubber is an elastomer manufactured from latex, the milky sap of the rubber tree. Petroleum is used to make synthetic elastomers. Rubber is frequently referred to as elastomers because of this feature.

Question 4: What is Neoprene?

Answer:

Neoprene, also known as polychloroprene, is a homopolymer formed by the polymerization of chloroprene by free radicals. It is used to create conveyor belts, hoses, and gaskets, among other things, and has a high oil resistance.

Question 5: What is Buna-S?

Answer:

Buna – S is made up of 1,3-butadiene and styrene copolymerized together. It has a high tensile strength and can be used as a replacement for natural rubber. It’s used to make products like vehicle tyres, footwear components, cable insulators, and more.


My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!