Natural Rubber (NR)
Chemical Structure: Cis-Poliisoprene
Characteristics: Excellent elastic yield and resistance to wear and abrasion, to cut and laceration. Exceptional extension at break. Negative characteristics: insufficient resistance to ageing, oil and heat. Negative behavior when there are ozone, strong acidics, fats, oil and hydrocarbon. Chemical resistance: not bad resistance to seawater, acidics and alkali with medium concentration.
Styrene-Butadiene Rubber (SBR)
Chemical structure: Styrene-Butadiene
Denomination: Styrene-Butadiene Rubber
Characteristics: Inexpensive rubber with good physical features and good resistance to abrasion. Negative characteristics: limited reistance to ageing (Ozone) and negative behavior when there are oils, fats, strong acidics and hydrocarbon. Limited resistance to high temperatures. Chemical resistance: not bad resistance to seawater, acidics and alkali with medium concentration.
Chloroprene(CR)
Chemical structure: Chloro Butadiene
Denomination: Neoprene
Characteristics: not bad resistance to oil. Excellent resistance to ozone, seawater and ageing. Good resistance to cut, abrasion and combustion. Negative characteristics: it tends to remove the hydrochloric acid and consequently there will be the corrosion of possible metals in contact. Negative behavior when there are concentrated oxidizing acids, ester, ketone, chlorinated, aromatic and nitric hydrocarbon. Chemical resistance: oil-rich products, solar light and atmospheric agents, ozone and flame.
Ethylene-Propylene Copolymer (EPM)
Chemical structure: Ethylene-Propylene
Denomination: Dutral CO
Characteristics: Excellent resistance to heat, atmospheric agents and ageing. Low-temperature embrittlement. Chemical resistance: Good resistance to aggressive chemicals and oxygenation.
EPDM
Chemical structure: Ethylene-Pylene Terpolymer
Denomination: Dutral TER, EPDM
Characteristics: Excellent resistance to heat, atmospheric agents and ageing. The braking temperature is low. Negative characteristics: it has a bad behavior when it is in contact with mineral oil, solvents and hydrocarbon. Chemical resistance: Good resistance to aggressive chemicals and oxygenation. Excellents resistance to vapor.
Nitrile or Oilproof rubber (NBR)
Chemical structure: Butadiene acrylonitrile Copolymer
Denomination: Nitrine or Oilproof
Characteristics: Excellent resistance to oil, heat and ageing. Good mechanical features. Low permanent deformation and low permability to gas. Negative characteristics: limited resistance to ozone, ketone, aldehyde ester and Chlorinated. Insufficient dielectric feature. Low resilience. Chemical resistance to mineral oil, hydrocarbur, water, vapor, gas and vegetal oil.
Silicone (VMQ)
Chemical structure: Polidimetilsilossano
Denomination: Silicone
Characteristics: Perfect behavior when there are high and low temperature. Excellent resistance to atmospheric agents and ozone. Excellent behavior to the residual deformation after the compression. Negative characterisitcs: modest mechanical features. Bad behavior when it is in contact with oil, gasoline and fuel generally. Chemical resistance to chloride, solvents, UV rays, ozone, oxygen, cold and heat, physiological liquids, oxidizing substances.
Viton (FKM)
Chemical structure: Esafluoroppropilene
Denomination: Viton
Characteristics: Excellent resistance to chemical attack and perfect resistance to lubricants and heat. Good behavior to compression-set and flexible performance. Excellent resistance to chemical products. Negative characteristics: insufficient chemical resistance to alkali and ketone. Chemical resistance to solar light and flame. High temperature. Aromatic and aliphatic hydrocarbur. Aggresive chemicals and chlorinated solvents.
Urethane rubber (PU)
Chemical structure: polyurethane
Denomination: Vulkollan
Characteristics: Very high resistance to abrasion, traction, curve, and oils. Negative characteristics: Insufficient resistance to water, alkali and acids. Chemical resistance to oil-rich products.
FEATURES OF THE RUBBER COMPOUNDS |
EPDM |
FKM |
SBR |
FLUIDS |
Resistance to oils derivative of petroleum |
excellent |
very good |
not suitable |
Aliphatic solvents |
not suitable |
excellent |
very good |
not suitable |
Aromatic solvents |
not suitable |
excellent |
quite good |
not suitable |
Ketone |
lousy |
weak |
not suitable |
lousy |
Chlorinated solvents |
not suitable |
excellent |
lousy |
not suitable |
Water |
incredibly good |
excellent |
quite good |
good |
Gas impermeability |
lousy |
incredibly good |
quite good |
lousy |
Diluted acids |
excellent |
excellent |
quite good |
good |
Concentrated acids |
excellent |
excellent |
lousy |
lousy |
Strong oxidizing acids |
quite good |
excellent |
not suitable |
not suitable |
Resistance to ageing |
Air |
incredibly good |
incredibly good |
quite good |
quite good |
To light |
incredibly good |
incredibly good |
lousy |
lousy |
To ozone and atmospheric agents |
excellent |
excellent |
not suitable |
weak |
Resistance |
To fire |
not suitable |
incredibly good |
lousy |
not suitable |
To heat |
incredibly good |
excellent |
quite good |
quite good |
To cold |
excellent |
quite good |
weak |
good |
Mechanics |
Traction |
quite good |
good |
good |
good |
Laceration |
incredibly good |
incredibly good |
lousy |
good |
Compression |
good |
quite good |
good |
quite good |
Abrasion |
incredibly good |
incredibly good |
good |
incredibly good |
Curve |
lousy |
quite good |
good |
good |
Resilience |
weak |
weak |
lousy |
good |
Electrical isolation |
Resistance |
excellent |
lousy |
weak |
good |
Dielectric (isolating) |
incredibly good |
lousy |
lousy |
quite good |
