Urethane
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Common Name
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Urethane, Polyurethane
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ASTM D-2000 Classification
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BG
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Military (MIL STD 417)
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SB
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Chemical Definition
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Polyester/Polyether Urethane
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General Characteristics
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Durometer Range (Shore A)
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35 - 100
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Tensile Range (P.S.I.)
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500 - 6000
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Elongation (Max. %)
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750
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Compression Set
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Poor
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Resilience - Rebound
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Good
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Abrasion Resistance
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Excellent
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Tear Resistance
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Excellent
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Solvent Resistance
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Poor
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Oil Resistance
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Good
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Low Temperature Usage (F°)
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-10° to -30°
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High Temperature Usage (F°)
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to 175°
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Aging Weather - Sunlight
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Excellent
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Adhesion to Metal
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Fair to Good
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Comment
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The castable types have excellent abrasion resistance; good compression set at high hardness levels; low friction surface; tensile strengths up to 6000 PSI; good ozone resistance; good oil and solvent resistance; and poor heat and hot water resistance.
The millable types of Polyurethane are in wide use today. Through the use of reinforcing pigments and other chemicals, desirable characteristics can be obtained to fit a variety of applications; wear resistance is excellent and greatly superior to most other polymers; the surface is of low friction nature; oil resistance is good and equivalent to the better nitriles but is not recommended for use in water or heat above 175°F.; plus good ozone resistance and low rebound characteristics.
Urethane is not normally attacked by moderate chemicals and hydrocarbons. It is generally attacked by concentrated acids, ketones, esters, chlorinated and nitro hydrocarbons.
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