I.Core Properties of Common Rubbers
II.Differences and Applications of Common Rubbers
Note:
Practical rubber products often contain pigments, so color cannot be used as the sole basis for identification.
The most reliable methods are:
– Checking the material marking (e.g., markings on oil seals)
– Consulting your supplier
For simple identification, you can combine:
– Oil resistance test (observe swelling after immersion)
– Burning characteristics (e.g., CR is self-extinguishing)
III.Advantages and Disadvantages of Common Rubbers
Natural Rubber (NR)
Main Advantages: Excellent elasticity, tensile strength, and tear resistance; good processability.
Main Disadvantages: Poor resistance to oil, ozone, and heat aging; narrow operating temperature range.
Styrene-Butadiene Rubber (SBR)
Main Advantages: High abrasion resistance, heat resistance, low cost, and the highest production volume.
Main Disadvantages: Slightly lower elasticity and cold resistance; poor resistance to oil.
Butadiene Rubber (BR)
Main Advantages: Outstanding elasticity, abrasion resistance, and cold resistance.
Main Disadvantages: Poor tear resistance.
Chloroprene Rubber (CR)
Main Advantages: Good overall performance; resistant to oil, weathering, flame, and ozone aging.
Main Disadvantages: High density, average low-temperature performance, and relatively expensive.
Nitrile Rubber (NBR)
Main Advantages: Excellent oil resistance (second only to fluorocarbon rubber, etc.), good abrasion resistance, and airtightness.
Main Disadvantages: Poor cold resistance, ozone resistance, and electrical insulation.
Ethylene Propylene Diene Monomer (EPDM)
Main Advantages: Superior resistance to ozone, weathering, and aging; resistant to hot water and steam; good electrical insulation.
Main Disadvantages: Poor oil resistance; slow vulcanization; poor self-adhesion.
Butyl Rubber (IIR)
Main Advantages: Best gas and water tightness; heat and aging resistance.
Main Disadvantages: Poor tack, slow vulcanization, and poor oil resistance.
Silicone Rubber (SI)
Main Advantages: Widest temperature resistance range, non-toxic, insulating, and ozone-resistant.
Main Disadvantages: Low mechanical strength, poor oil and solvent resistance, and high cost.
Fluorocarbon Rubber (FKM)
Main Advantages: High-temperature resistance, oil resistance, superior chemical resistance, and aging resistance.
Main Disadvantages: Very expensive, poor processability, average cold resistance, and low elasticity.
Chlorosulfonated Polyethylene (CSM)
Main Advantages: Excellent abrasion resistance, weather resistance, ozone resistance, and good flame retardancy.
Main Disadvantages: High cost, poor rebound, and compression set properties.
IV. Quick Selection Guide
Great elasticity → Choose Natural Rubber (NR)
Great wear resistance & low cost → Choose Styrene-Butadiene Rubber (SBR)
Oil resistance → Choose Nitrile Rubber (NBR) (general use) or Fluoro Rubber (FKM)(extreme conditions)
Weather & aging resistance → Choose Ethylene Propylene Rubber (EPDM)
Air & water tightness → Choose Butyl Rubber (IIR)
Wide temperature resistance → Choose Silicone Rubber (SI)
Super corrosion resistance → Choose Fluoro Rubber (FKM)
