RPTFE Vs. EPDM Specificationsby Manny Jeter
EPDM stands for ethylene propylene, while RPTFE stands for reinforced polytetrafluoroethylene. RPTFE is also known as reinforced teflon. Both EPDM and RPTFE are organic compounds with well sought-after properties. The compounds are resistant to other harmful compounds, making them useful for many applications. The automobile industry is the main user of both compounds.
EPDM is resistant to water, chemicals, gas and heat. The compound is resistant to temperature of up to 302 degrees Fahrenheit. RPTFE is resistant to aggressive chemicals, fillers, and nitrogen tetroxide, also known as highly oxidizing media. RPTFE's heat resistance is superior EPDM's since it has a heat resistance of up to 520 degrees Fahrenheit.
EPDM has an elongation of up to 600 percent while RPTFE has an elongation of up to 300 percent. Elongation refers to how far the material can be stretched before breaking. EPDM has a hardness range of 30 to 95 and RPTFE has a hardness range of 50 to 55. EPDM has a tensile strength from 1 to 3 PSI and a specific gravity of 0.88 gm/ml, while RPTFE has a tensile strength of 4,000 PSI and a specific gravity of 2.2 gm/ml. Tensile strength defines how much force is required to pull the material to a point where it breaks or snaps. Specific gravity defines how dense a material by comparing it to water.
EPDM is used in automotive weather stripping and seals, radiators, tubing, belts, garden hose, electrical insulation, roofing membrane, motor oil additives, brake systems, and much more. RPTFE is used on ball valve systems, drilling parts, washers, conveyor slides, conveyor guide rails, gaskets and much more. RPTFE is also used in laboratories by scientists who use it for tubing, containers, and vessels because of its chemical resistance.
RPTFE is a chalky-white color while EPDM is black. RPTFE is 15 precent glass filled and normal PTFE that has no filler. RPTFE is recommended for food applications and products that need resistance to heat, chemicals, and acids while EPDM is not. RPTFE was discovered in 1938 and EPDM has been known since at least the 1500s.
- link Plastomer Technologies: PTFE Properties:
- link Azom: Ethylene Propylene Rubbers -- Properties and Applications of Ethylene Propylene Diene (EPDM) and Ethylene Propylene Copolymers (EPM)
- link Cam-Tite Seat Design
- link DKI Rubber: Ethylene-Propylene (EPDM)
- link Tru-Flo: Ball Valve Seat Material Guide
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