Product Info
Rubber Materials
Characteristic by Material
NBR(Acrylonitrile Butadiene Rubber)
NBR is widely used as materials for sealing parts on vehicles. NBR’s performance, processability and price is better than other materials. Heat and oil resistance ability rise as polymer structure and acryl group rise, cold-resistance ability rise as butadiene group rise. So these abilities can be controlled by changing the ratio of copolymerization.
Physical characteristics such as hardness, compression set is excellent but ozone-resistance and heat-resistance ability is poor.
Usable temperature range : -20 ℃ ~ +110 ℃ (high nitryl), -40 ℃ ~ +100 ℃ (low nitryl)
H-NBR
H-NBR is made by high-hydriding of butadiene double bond to complement shortages of NBR such as poor specification on high temperature and long life time. H-NBR’s compression set, hardness, oil and heat resistance ability is better than NBR. H-NBR’s cold-resistance ability is poor and the cost is high.
Expansion of usage is expected, and recently improved cold-resistance ability H-NBR is studied by copolymerize the third material.
Usable temperature range : -35 ℃ ~ +140 ℃
FKM (Fluoroelstomer)
Ternary System
FKM has the best heat, oil and fuel resistance abilities above all rubber materials, but poor cold-resistance and high cost.
Binary system polymer is composed of vinylidene fluoride and six fluoro propylene, and ternary system polymer is composed of vinylidenefluoride and sixfluoropropylene, tetrafluoroethylene as an improved oil-resistance case. Fluorine content is about 66%~70%.
Generally, heat and oil resistance rises as fluorine content rises but cold-resistance falls. ACM and VMQ are widely used as sealing parts in driving system. But usage of FKM is expanded for high performance and long life time. Also studies show that special fluoro rubber can stand up to 300℃ but the cost is a problem.
Usable temperature range : -20 ℃ ~ +230 ℃
ACM (Acrylic Rubber)
ACM is composed of Acrylic acid ester mainly, and compare to a wide use dien group, it has high oil, heat, ozone resistance because it has high polarity ester side chain on ethylene main chain. It is used widely to prevent leakage of lubricants.
Study show that compression set improved, and also can be applied to O-rings and Gaskets.
Usable temperature range : -30 ℃ ~ +160 ℃
VMQ (Fluoroelastomer)
VMQ is a wide use silicone rubber which has metyl group on siloxane main chain. Resistance to heat, cold, lubricant and water is excellent and it is easy to dye because 저경재 design is possible. It’s physical hardness is poor, and can be hydrolyze by alkalinity or acid, so it’s performance could be poor even in usable temperature range. It is widely used for engine seals. However due to hydrolysis problems, it is being replaced by FKM materials.
Usable temperature range : -70 ℃ ~ +200 ℃
Stability to various kinds of fluid for each materials
※ introductory remarks : ☆ (Excellent), O(good), △(normal), X(bad)
|
various kinds of fluid
Name of fluid
|
NBR | H-NBR | ACM | VMQ | FKM | EPDM | SBR | Etc | |
|---|---|---|---|---|---|---|---|---|---|
| Engine oil | ☆ | ☆ | ☆ | ○ | ☆ | X | X | ||
| Gear oil for vehicle | ☆ | ☆ | ☆ | △ | ○ | X | X | ||
| Gasoline | △ | ○ | X | X | ○ | X | X | ||
| Diesel/kerosene | △ | ○ | X | X | ☆ | X | X | ||
| Heavy oil | ○ | ☆ | △ | X | ☆ | X | X | ||
| Break oil | DOT3 (glycol) | △ | X | X | ○ | X | ○ | ○ | |
| DOT5 (glycol) | △ | X | X | ○ | X | ○ | ○ | ||
| DOT5 (silicone) | ☆ | ☆ | ☆ | X | ☆ | ○ | ○ | ||
| Hydraulic fluid(mineral oil) | ☆ | ☆ | ☆ | ○ | ☆ | X | X | ||
| Cutting oil | ○ | ☆ | △ | △ | ☆ | X | X | ||
| Grease | Mineral oil | ☆ | ☆ | ☆ | ☆ | ☆ | X | X | |
| Silicone | ☆ | ☆ | ☆ | X | ☆ | ☆ | ○ | ||
| Fluorine | ☆ | ☆ | ☆ | ☆ | △ | ☆ | ○ | ||
| Refrigerant | R12(paraffin) | ○ | ☆ | X | X | X | X | X | |
| R134a(glycol) | △ | ○ | X | X | X | ☆ | X | ||
| Antifreeze | ○ | ○ | X | △ | X | ☆ | ☆ | ||
| Water(Hot) | ○ | ☆ | X | ○ | ○ | ☆ | ☆ | ||
| Steam | X | ○ | X | X | X | ○ | △ | ||
| Ethanol | ○ | ○ | X | ○ | ○ | ☆ | ☆ | ||
| MEK | X | X | X | △ | X | X | X | ||
