Rubber Materials - KEF America | for micro rubber molding and more.

FDA and Aviation Grade Rubber Material

KEF develops and formulates our rubber materials in-house. We use our extensive skills in applied material technology to give our customers a competitive advantage.

We draw from the latest material technologies and many thousands of our own rubber compounds from our material databases. Our materials group develops your material according to specification in timely manner. KEF provides FDA compliant medical grade materials, as well as aviation materials per AMS-P-5315.

Standard Rubber Materials

Natural Rubber (NR)

Chemical Structure: Polyisoprene

Mechanical properties such as the elasticity, wear and abrasion resistance are good.

Styrene-Butadiene Rubber (SBR)

Chemical Structure: Styrene and butadiene copolymer

Wear, abrasion, and aging resistance are better than natural rubber.

Butadiene Rubber (BR)

Chemical Structure: Polybutadiene

Elasticity is good. Wear and abrasion resistance are also superior to natural rubber.

Neoprene/Chloroprene Rubber (CR)

Chemical Structure: Poly chloroprene

Weatherability, ozone resistance, heat resistance, and chemical resistance, are excellent.

Butyl Rubber/Isobutylene-Isoprene Rubber (IIR)

Chemical Structure: Isobutylene isoprene copolymer

Weatherability, ozone resistance, and gas-proof permeability are good, and bears a polar solvent.

Nitrile Rubber (NBR)

Chemical Structure: Butadiene-acrylonitrile copolymer

Oil, wear. abrasion, and aging resistance are good.

Ethylene-Propylene (EPM, EPMD)

Chemical Structure: Ethylene proplene copolymer

Aging resistance, ozone resistance, the resistance over a polar liquid and electric nature are good.

Acrylic Rubber (ACM ANM)

Chemical Structure: Acrylic ester copolymer

Good for high temperature oil resistance.

Polyurethane Rubber (U)

Chemical Structure: Polyurethane

Polyurethane excels in dynamic intensity. Polyurethane has good biocompatibility and is commonly used in biomedical devices.

Silicone Rubber (Q)

Chemical Structure: An organic polysiloxane

Silicone has excellent resistance to heat and cold. Oil resistance is also good. Silicone has very good biocompatibility, making it a preferred choice for medical device.

Fluorocarbon Rubber (FKM)

Chemical Structure: Perfluoropropene, vinylidene fluoride copolymer

This rubber material has the highest resistance to heat and cold.

Material Properties

Rubber Kind	Natural Rubber (NR)	Styrene-Butadiene Rubber (SBR)	Butadiene Rubber (BR)	Chloroprene Rubber (CR)	Isobutylene-Isoprene Rubber (IIR)	Nitrile Rubber (NBR)	Ethylene-Propylene (EPM, EPMD)	Acrylic Rubber (ACM ANM)	Urethane Rubber (U)	Silicone Rubber (Q)	Fluorocarbon Rubber (FKM)
Specific Gravity	0.92	0.92 to 0.97	0.91 to 0.94	1.15 to 1.25	0.91 to 0.93	0.96 to 1..02	0.86 to 0.87	1.09 to 1.10	1.00 to 1.30	0.95 to 0.98	1.80 to 1.82
Mooney Viscosity	45 to 150	30 to 70	35 to 55	45 to 120	45 to 80	30 to 130	40 to 100	45 to 60	25 to 26 or Liquefied	Liquefied	35 to 160
Tensile Strength (kgf/cm^2)	30 to 350	25 to 300	25 to 200	50 to 250	50 to 200	50 to 250	50 to 200	70 to 120	200 to 450	30 to 120	70 to 200
Extension (%)	1000 to 100	800 to 100	800 to 100	1000 to 100	800 to 100	800 to 100	800 to 100	600 to 100	800 to 300	500 to 50	500 to 100
Rebound Resilience	Excellent	Good	Excellent	Excellent	Fair	Good	Good	Fair	Excellent	Excellent	Fair
Strength of Tears	Excellent	Fair	Good	Good	Good	Good	Fair	Fair	Excellent	Poor to Fair	Good
Wear Resistance	Excellent	Excellent	Excellent	Good to Excellent	Good	Excellent	Good	Good	Excellent	Poor to Fair	Excellent
Crookedness-proof Crack Nature	Excellent	Good	Fair	Good	Excellent	Good	Good	Good	Excellent	Poor to Good	Good
Usable Temp (C)	-75 to 90	-60 to 120	-100 to 120	-60 to 120	-60 to 150	-30 to 130	-60 to 150	-30 to 180	-60 to 80	120 to 280	-50 to 300
Aging Resistance	Good	Good	Good	Excellent	Excellent	Excellent	Excellent	Excellent	Good	Excellent	Excellent
Lightfastness	Good	Good	Good	Excellent	Excellent	Good	Excellent	Excellent	Excellent	Excellent	Excellent
Ozone Resistance	Poor	Poor	Poor	Excellent	Excellent	Poor	Excellent	Excellent	Excellent	Excellent	Excellent
Fire Resistance	Poor	Poor	Poor	Good	Poor	Poor to Fair	Poor	Poor to Fair	Poor to Fair	Poor to Good	Excellent
Electronic Insulation (ocm cm)	10^10	10^10	10^14	10^10	10^15	10^2	10^12	10^8	10^8	10^11	10^10
Volume Specific Resistance	~10^15	~10^15	~10^15	~10^12	~10^18	~11^11	~10^16	~10^10	~10^12	~10^16	~10^14
Gas Permeability	18	12	13 to 50	3	0.9 to 1.0	0.3 to 3.5	15	10	2	400	1
Radiation Resistance	Fair to Good	Good	Poor	Fair to Good	Poor	Fair to Good	Poor	Poor to Fair	Good	Fair to Excellent	Fair to Good
Gasoline and Light Oil Resistance	Poor	Poor	Poor	Good	Poor	Excellent	Poor	Excellent	Excellent	Poor to Fair	Excellent
Benzene, Toluene Resistance	Poor	Poor	Poor	Poor	Fair to Good	Poor to Fair	Fair	Poor	Poor to Fair	Poor to Fair	Excellent
Trichloroethylene Resistance	Poor	Poor	Poor	Poor	Poor	Poor	Poor	Poor	Fair to Good	Poor to Good	Good
Alcohol Resistance	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent	Poor	Fair	Excellent	Excellent
Ether Resistance	Poor	Poor	Poor	Poor to Fair	Fair to Good	Poor to Fair	Good	Poor	Poor	Poor to Fair	Poor to Fair
Ketone (MEK) Resistance	Fair to Good	Fair to Good	Fair to Good	Fair to Good	Excellent	Poor	Excellent	Poor	Poor	Good	Poor
Ethyl Acetate Resistance	Poor to Fair	Poor to Fair	Poor to Fair	Poor	Excellent	Poor to Fair	Excellent	Poor	Fair	Fair to Excellent	Poor
Water Resistance	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent	Fair	Fair	Good	Excellent
Organic Acid Resistance	Poor	Poor	Poor	Poor	Fair to Good	Poor to Fair	Poor	Poor	Poor	Good	Poor
High Concentration Inorganic Acid Resistance	Fair	Fair	Fair	Good	Excellent	Good	Good	Fair	Poor	Fair	Excellent
Low Concentration Inorganic Acid Resistance	Good	Good	Good	Excellent	Excellent	Good	Excellent	Good	Fair	Good	Excellent
High Concentration Alkali Resistance	Good	Good	Good	Excellent	Excellent	Good	Excellent	Fair	Poor	Excellent	Poor

Generated by wpDataTables

Custom Rubber Materials

KEF provides over 50 years of extensive experience in rubber materials and moldings. We develop custom rubber compounds to meet complex needs.

For example, our Delta KB, KE, KF have been developed by request specifically for the hard disk industry . These materials are Non-siloxane and low outgassing compounds developed from IIR, EPDM, FKM.

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