Polyurethane, Cast

Trade Names:

  • Vibrathane . . . Uniroyal
  • Cyanaprene . . . American Cyanamid
  • Polathane . . . Polaroid

ASTM D1418 Designation: N/A

ASTM D2000/SAE J200 Type, Class: N/A

Apple Compound Designation: CP

Standard Color: Amber

Description: Cast Polyurethane is outstanding over other O-ring elastomers in abrasion resistance and tensile strength. Additionally, Cast Polyurethane surpasses the performance of Millable Polyurethane in its higher tensile strength, greater elongation, wider temperature range, and lower compression set characteristics.

Key Use(s): Seals for high hydraulic pressures. Situations where highly stressed parts are subject to wear. Used for wheels, rolls, slurry parts, bumpers, couplers, and shock absorbers. Wiper seals for axially moving piston rods.

Temperature Range: Standard Compound: -30° to +175°F.

Hardness (Shore A): 70 and 90.

Features: With tensile strength of up to 6,000 psi, elongation of 350 to 650%, compression sets of 10 to 25%, and exceedingly high abrasion resistance, the physical properties of Cast Polyurethane are among the best of all O-ring elastomers.

Although they swell slightly upon exposure, Cast Polyurethane compounds feature excellent resistance to mineral-based oils and petroleum products, aliphatic solvents, alcohols and ether. They are also compatible with hydraulic fluids, weak acids and bases, and mixtures containing less than 80% aromatic constituents.

Limitations: Cast Polyurethanes are not recommended for exposure to concentrated acids and bases, ketones, esters, very strong oxidizing agents, pure aromatic compounds and brake fluids. With the exception of special compounds, they are also not recommended for exposure to hot water or steam.