Rubber can be broadly classified into two main categories: natural rubber and synthetic rubber. Each category contains various types and classes based on their properties and applications.
1. Natural Rubber
Natural Rubber (NR)
- Source: Derived from the latex of the Hevea brasiliensis tree.
- Properties: High tensile strength, elasticity, resilience, and resistance to abrasion.
- Applications: Tires, hoses, belts, footwear, and medical supplies.
2. Synthetic Rubber
Synthetic rubbers are man-made polymers produced through the polymerization of various monomers. There are several types of synthetic rubber, each with unique properties suited for specific applications.
Types of Synthetic Rubber:
- Styrene-Butadiene Rubber (SBR)
- Properties: Good abrasion resistance, aging stability, and cost-effective.
- Applications: Tires, footwear, and conveyor belts.
- Polybutadiene Rubber (BR)
- Properties: High resilience, wear resistance, and low heat build-up.
- Applications: Tires, golf balls, and various rubber goods.
- Nitrile Rubber (NBR)
- Properties: Excellent oil and fuel resistance, good abrasion resistance.
- Applications: O-rings, seals, hoses, and gloves.
- Ethylene Propylene Diene Monomer (EPDM)
- Properties: Excellent weather, ozone, and heat resistance, good electrical insulating properties.
- Applications: Automotive weatherstripping, roofing membranes, and hoses.
- Chloroprene Rubber (CR)
- Properties: Good flame, weather, and oil resistance, moderate flexibility.
- Applications: Wetsuits, gaskets, and automotive parts.
- Butyl Rubber (IIR)
- Properties: Excellent impermeability to gases, good flex properties, and resistance to chemicals.
- Applications: Inner tubes, seals, and pharmaceutical stoppers.
- Acrylonitrile Butadiene Styrene (ABS)
- Properties: High impact resistance, good chemical resistance.
- Applications: Automotive parts, consumer goods, and toys.
- Silicone Rubber (Q)
- Properties: Exceptional heat and cold resistance, excellent electrical insulation.
- Applications: Medical devices, cookware, and seals.
- Fluoroelastomers (FKM)
- Properties: Excellent heat, oil, and chemical resistance.
- Applications: Aerospace, automotive, and chemical processing seals.
- Polyurethane Rubber (AU/EU)
- Properties: High abrasion resistance, good mechanical properties.
- Applications: Wheels, rollers, and seals.
Classifications Based on Applications and Properties:
- General-Purpose Rubber: SBR, NR, and BR are commonly used for general applications like tires and mechanical goods.
- Special-Purpose Rubber: NBR, CR, EPDM, IIR, and silicone rubbers are used where specific properties like oil resistance, weather resistance, and gas impermeability are needed.
- High-Performance Rubber: Fluoroelastomers and polyurethane rubbers are used in high-performance applications requiring exceptional resistance to harsh environments and mechanical stress.
Each type and class of rubber is selected based on its specific properties to meet the demands of different industrial applications.