NR – Natural Rubber
The milky white liquid in the bark of the rubber tree is called “Latex”. Rubber is obtained from 30-40% of the collected liquid. The regular structure of natural rubber positively affects its physical properties. Another important characteristic of natural rubber is that its structure remains smooth under load and tension. Because of this property, its tensile strength increases even without reinforcing fillers.
The operating temperature range is -60°C to 90°C.
Physical Properties:
- High tensile strength
- High tear strength
- High raw rubber strength
- High elasticity values
- High dynamic values
- High permanent deformation values
Application Environment:
- Water-like environments with low temperatures
- Glycol-based oils
Application Areas:
- Mechanical parts
- Vibration and impact damping parts
- Bushings
- Vibration damping connections
- Engine parts
- Shoe soles
- Hoses
- Conveyor belts
- Floor coverings
- Sponge
- Adhesives
SBR – Styrene Butadiene Rubber
It is the most widely used, low-cost synthetic rubber in the world. The compound has an irregular structure. It can be used as a substitute for natural rubber.
Operating temperature range: -50°C to 100°C.
Physical Properties:
- Easy to process
Processable in a short time - Suitable for extrusion processing
- Low elasticity values
- High abrasion resistance
- High aging resistance
Application Environment:
- Solvent chemicals
- Glycol-based brake fluids
- Bases
Application Area:
- Vehicle tires
Light-colored technical materials - Extrusion materials
- Cables and electrical materials
- Brake and clutch linings
- Transparent tapes
- Adhesives
- Dynamic parts (V-belts)
EPDM – Ethylene Propylene Diene Rubber
Due to its low density, it is used in the production of lightweight materials. It offers the possibility of making low-cost mixtures. Its good physical properties at high additive ratios, low specific gravity, and fast mixing, extrusion, and vulcanization capabilities are among its production advantages.
It can be used between -40°C and 150°C.
Application Environment:
- Aqueous and concentrated acids
- Alkalis
- Silicone fluids
- Hot water and steam
- Phosphate ester-based non-flammable hydraulic fluids
Application Area:
- Insulating material in high-voltage cables
- Door and window insulation
- Radiator and heater hoses
- Bellows and gaskets for white goods and automotive
- Conveyor belts
- Insulation for water and chemical tanks
NBR – Nitrile Rubber
It is formed by mixing acrylonitrile and butadiene monomers with the help of auxiliary additives. The acrylonitrile ratio in the mixture determines the properties of the material. Generally, the acrylonitrile ratio in the mixture ranges from 18% to 50%. Acrylonitrile gives the mixture polar properties, reducing its solubility to hydrocarbons.
As the acrylonitrile ratio in the mixture increases, the material’s resistance to oils, fuels, lubricants, greases, and gases increases. Its density, hardness, and curing speed increase. The mixture’s machinability improves. Its mechanical properties improve. Its elasticity coefficient, permanent durability value, resistance to aging, fatigue, and wear increase, and its service life is extended.
As the acrylonitrile ratio in the mixture decreases, the material’s resistance at low temperatures decreases. Permanent deformation values worsen. Elasticity decreases. Production becomes more difficult. It is a material most commonly used for general-purpose sealing, preferred in the manufacture of sealing elements, and offers a cost-effectiveness based on its functions.
Suitable for use between -40°C and 100°C.
Applications:
- Sealing elements
- Pneumatic hoses
- Connecting elements
- Conveying belts
- Cylinder coatings
- Work clothes and boots
- Rubber plates and seals
- Couplings, membranes, gasoline, oil and hydraulic hoses
VMQ – Silicone Rubber
Unlike polymer rubbers, it consists of silicon and oxygen bonding systems. Despite the weak bonding forces, it has a stable structure. The resulting bond structures are expressed with the letter “Q”. The naming varies depending on the auxiliary materials used during its preparation. If the silicone rubber mixture is prepared with methyl (CH₃ – Saturated Hydrocarbon), it is expressed with “MQ”; if prepared with methyl vinyl (Saturated and Unsaturated Hydrocarbon), it is expressed with “VMQ”; and if prepared with phenyl methyl (Organic Hydrocarbon and Saturated Hydrocarbon), it is expressed with “PMQ”. It has excellent resistance to ultraviolet rays, ozone, external factors, air, and moisture.
It can be used between -50°C and 200°C.
Application Environment:
- High ultraviolet resistance
- Superior ozone resistance
- Resistant to external factors
- Air and moisture resistance
- Superior insulation properties
- Flammability
- Very good aging resistance
- Long lifespan
- High durability even underground
- Can be processed transparently
- Very good elasticity properties
- Easily paintable
- Non-toxic
- Physiologically harmless
- An expensive material
Application Area:
- Cables, cable ends, insulators and switches
- Spark plug wires and caps
- Radiator hoses and insulation elements
- Insulated brake diaphragms
- Baby pacifiers
- Gas masks
- Sealing gaskets for ovens
- Sealing gaskets for refrigerators
- Sealing gaskets for ozone units and systems
FKM – Fluoro Elastomer Rubber
It has excellent resistance to high temperatures, oils, and fuels. It can operate at high temperatures. It has low swelling properties. It is resistant to aromatic hydrocarbons, oils, greases, chemicals, acids, petroleum oils, and solvents. It has high resistance to oxygen and ozone. It is resistant to combustion; it is non-flammable. It has low gas permeability. It is a difficult and expensive rubber material to process. It is not suitable for contact with food.
It can be used between -30°C and 250°C.
Application Environment:
- Aromatic hydrocarbons
- Fuels
- Oils
- Greases
- Acids
- Petroleum oils
- Solvents
Application Area:
- Aerospace industry
- Automotive industry
- Cylinder coating
HNBR – Hydrogen Nitrile Rubber
HNBR fills the gap between NBR, EPDM, and FKM (Viton) where high tensile strength is required under high-temperature conditions, while maintaining excellent resistance to motor oils, acidic gases, amine/oil mixtures, oxidized fuels, and machine oils.
Fully saturated NBR types can cross-link with peroxides. These peroxide cross-links along the double bond enhance thermal stability and oxidation balance.
Vulcanizates provide the highest hot air and hot oil resistance, oxidative and ozone decomposition resistance, resistance to sulfur-containing oils, resistance to sulfur and nitrogen-containing oil additives (including hydrogen sulfide), and resistance to industrial chemicals achievable with NBRs.
The material is characterized by high mechanical strength and improved wear resistance.
It is used between -30°C and 150°C.
ACM – Polyacrylic Rubber
ACM is obtained by copolymerizing acrylic esters with monomers. The acrylic esters used are ethyl acrylate and/or butyl or octyl acrylate, ethylmethoxy or ethyloxy acrylate. These copolymers are highly resistant to oil, heat, aging, and ozone.
The tensile properties of acrylic rubbers are not as good as those of NR and NBR. Newer generation ACMs, in particular, can operate for up to 1000 hours at around 160-170°C. However, they soften at high temperatures.
ACM vulcanizates are more resistant to swelling in animal, vegetable, and mineral oils than other rubbers, except for FKM, although this resistance decreases with increasing temperature. Their resistance to chemicals is also not very good. They have poor dry-running properties and are not suitable for use at low temperatures or in water.
More than 90% of ACM products are used in the automotive industry. They are commonly used in crankshafts, as shaft seals in automatic and differential transmissions, and also in O-rings, valves, and oil hoses. Although their high price overshadows their other properties, fluoroelastomers (FKM) are preferred in many applications.
They are used between 160°C and 170°C.
CR – Chloroprene Rubber
Polar properties are good. It is resistant to many oils and flames. It has low gas permeability. It has strong adhesion to textile and metal materials. It has very good abrasion resistance. It has superior mechanical properties.
Operating temperature range is -20°C to 120°C.
Physical Properties:
- Resistant to oils
- Resistant to air and ozone
- Water resistant
- Resistant to chemicals
- Resistant to acids
Application Areas:
- Parts with a risk of combustion
- V-belts
- Rubber bellows
- Vibration damping elements
- Diving suits
- High-pressure hydraulic and brake hoses
- Seals