Rubber is a highly stretchable chemical compound that has elastic properties and mouldable nature. These elastomers are found in nature and extracted from plants. However, due to the huge demand for various types of rubber in the world, it is also widely manufactured as a synthetic polymer.
Natural rubber is extracted from rubber-producing trees such as Havea Brasiliense and Lactuca Sativa. Nowadays, 99% of natural rubber is extracted from Hevea brasiliensis. It is used in a wide variety of products, including tires, hoses, seals, and gaskets.
Synthetic rubber, on the other hand, is made from petroleum-derived monomers and is used in a variety of applications, including tires, hoses, belts, and seals. There are several different types of synthetic rubber, each with its own unique set of properties. For example, neoprene is known for its excellent resistance to oil and weathering, while silicone rubber is known for its high-temperature resistance and flexibility.
There are several different types of rubber available in the market. Some of the most popular are listed below:
1. Natural Rubber
- DL-limonene
- Isoprene
2. Vulcanized Rubber
3. Synthetic rubber
- Chlorosulphonated Polyethylene
- Neoprene Rubber
- Silicones
- Nitrile Rubber
- Nitrile butadiene Rubber
- Ethylene (EPDM) Rubber
- Styrene Butadiene Rubber
- Butyl Rubber
- Fluorosilicone Rubber
- Polychloroprene
- Polyurethane Rubber
- Polyacrylic Rubber
- Polyflouroelastomer Rubber
- Epichlorohydrin Rubber
Natural Rubber
Rubber trees are harvested all over the world to fulfill the need of society. Thailand is the largest rubber-producing country. Roughly, it produces 4 million tons of rubber naturally. These rubbers are used to produce tires as a main product and are also exported across the globe.
For example, limonene and isoprene are latex rubbers extracted from rubber trees.
Types of Synthetic Rubber
Vulcanized Rubber
Rubber is often made stronger by heating in the presence of sulfur. This process is known as vulcanization. This phenomenon is discovered by Charles Goodyear back in 1839. It takes place at 140ºC-160ºC and at high pressure. In this process, rubber forms new cross-links with sulfur which improves its elasticity durability non-stickiness, tensile strength, and resistance to the environment. They are used in sheds, toys, balls, and household items.
Neoprene Rubber
Neoprene is the trivial name of polychloroprene. It is a synthetic rubber. This can be prepared by the polymerization of chloroprene. It is a stable compound even at elevated temperatures. Due to this property, it is used In electrical insulations. It is also molded with pigments and other materials to create neoprene sheets.
Applications
- Electrical insulations
- Gaskets in engines
- Adhesives
- Conveyer belts
Silicone Rubber (SR)
Silicones are inorganic polymers. They have the backbone of silicon and oxygen with an organic group attached. Siloxanes are repeating units of silicones. They are colorless and non-toxic liquids.
Applications
- Automobile sealants
- Cooking utensils
- Grease
- Electronics
Nitrile Butyl Rubber
Nitrile butyl rubber is the derivative of acrylonitrile and butadiene. It contains unsaturation which permits vulcanization with sulfur. The common brand names are Perbunan® and Nipol®. Its production process is simple and takes place at 70ºC in one pot reaction. Its significant features of resilience against oil and chemical open up a wide range of applications in the oil and petroleum industry.
Applications
- Disposable gloves
- Seals (O-rings)
- Hoses and vessel covers
Ethylene (EPDM) Rubber
EPDM (ethylene-propylene-diene rubber) is a synthetic rubber. It is formed by the copolymerization of ethylene, propylene, and a diene in the presence of a Ziegler-Natta catalyst.
Precorsurs of EPDM
- Trans-1,4-hexadiene
- Dicyclopentadiene (DCP)
- Ethylidene norbornene
EPDM has perfect heat and weather-resistant properties. Therefore, it has applications in the following areas:
- Pool and tank lining
- Car bumpers
- Sealants of automobiles
- kitchen cabinets
Styrene Butadiene Rubber (SBR)
Styrene-butadiene rubber (SBR) is derived from styrene and butadiene. It is formed by two polymerization processes, one is solution polymerization and emulsion polymerization is the other. In solution polymerization, the reaction is initiated by anionic compounds such as alkyl lithium, while in emulsion polymerization, free radicals are initiators.
The major applications are given below:
- Tires industry: Almost 80% of tires around the globe are made up of SBR
- Shoe soles
- Adhesives
Butyl Rubber
Butyl rubber is made by the combination of isobutylene and isoprene. It is quite similar in structure to polypropelene. It was first prepared in WWII to meet the requirements of troops. Due to its excellent air retention properties, it is commonly used in inner tubes and inflatable products. It is also used in the synthesis of other types of rubber.
Further, it is also resistant to water and many chemicals, and it is an excellent electrical insulator. That is the reason for its application in a wide range of industries, including automotive, aerospace, construction, and medicine. Some more uses are given below:
- Tubeless tires (inner tubes)
- Sports (Tennis balls)
- Acid resistant gloves
- Waterproofing material
- As a liner in tanks and ponds
- Fuel additives
- Machining lubricants
Fluorosilicone Rubber (FR)
Fluorosilicones like silicone are highly stable elastomers. They are resistant to chemicals such as acids, alkalis, hydrocarbons, petroleum solvents, and amines.
Applications
- Aerospace industry
- Static sealing at a wide temperature range
- Compression sets
Polyurethane Rubber
Polyurethane, unlike silicones, is a foam-like structure. It is made by the combinations of diisocyanate and polyols in the presence of a catalyst. It is commercially available in two parts A and B. When A and B components are mixed together, they react with each other to form polyurethane. For example, a dishwashing sponge is a common example of polyurethane.
Some other applications are as follows:
- Clothes Polyurethane Fabrics
- Automobile seats
- Cleaning foams
- Adhesives
- cavity fillers
- Rocket fuels
- Abrasion resistant materials
Epichlorohydrin Rubber
Epichlorohydrin (ECH) rubber is a synthetic type of rubber that is highly resistant to water, chemicals, and heat. It is known for its good electrical insulating properties and low gas permeability. ECH rubber is used in a wide variety of applications, including seals, gaskets, and hoses in the automotive and aerospace industries, as well as in the production of adhesives and coatings. It is also used as a matrix material in the manufacture of composite materials.
Polymerized fluoroelastomers
It is the derivative of butadienes. Fluorine is added to the butenes in Ziegler Natta polymerization to enhance the performance of the polymer. It is commonly used in fluorescent plastics.
Related Topics
Key Takeaways
Concepts Berg
What are the different types of rubber?
Natural rubber, synthetic rubber, and cork are the three main categories of rubber. Types of synthetic rubber are given below:
- Vulcanized rubber
- Neoprene rubber
- Silicone
- Nitrile rubber
- Nitrile butadiene rubber
- Ethylene EPDM rubber
- Styrene-Butadiene rubber
- Butyl rubber
- Fluorosilicone rubber,
- polychloroprene
- Polyurethane rubber
- Polyacrylic rubber
- Polyflouroelastomer rubber
- Chlorosulphonated Polyethylene
- Epichlorohydrin rubber
What is natural rubber?
Natural rubber is a natural organic product released in the form of latex by plants. The common examples of natural rubber are given below:
- Lactuca sativa
- Ficus elastica
- Havia brasileenisis
What is synthetic rubber?
Synthetic rubber is a man-made elastomer. It is made up of petroleum and other chemical materials.
Why to install rubber flooring?
Rubber flooring is often advised for special purposes. For example, in some sophisticated labs where friction and hard surfaces may cause damage, as well as in child care centers.
How does rubber compare to polyurethane?
Polyurethane is more durable and highly efficient in advanced applications, such as making seals and gaskets in the automotive industry in general. On the other hand, rubber is also an elastomer but has a wider range of applications due to its low cost.
What is the strongest type of rubber?
The strongest rubber nitrile is also known as NBR (nitrile butadiene rubber). Their durability and resistance to chemical reactions are the foundations of their strength.
What are the five properties of rubber?
Properties of rubber:
- High tensile strength
- Durability
- Elastomer nature
- Resilience
- Abrasion resistance
How many types of rubber tires are there?
There are three types of rubber, as follows:
- Clincher
- Wired
- Tubular
How do you fuse rubber together?
To fuse rubbers, the best method is to heat them and join them. If there is a need for simple bonding, the best glue available is epoxy and acrylate adhesives.
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