For applications demanding exceptional chemical resistance, especially to acids, fuels, and oils, Master Bond has developed EP21AR. Whether coating, lining, bonding or sealing, this two-component epoxy can withstand harsh, acidic environments, including prolonged immersion in 96%-98% sulphuric acid and 36% hydrochloric acid for over a year.

With a dielectric strength of 400volts/mil, EP21AR is a durable and stable epoxy that is also a superb electrical insulator. Its coefficient of thermal expansion is 45ppm/°C to 55ppm/°C, and it is serviceable from -60°F to +275°F. It produces high strength, abrasion resistant bonds with a tensile strength over 10,000psi, a shear strength exceeding 2,700psi, and a compressive strength greater than 14,000psi at 75°F.

EP21AR is easy to use, with a forgiving 2:1 mix ratio by weight and a mixed viscosity of 10,000cps-15,000cps. It is 100% reactive, with no solvents or diluents, and can be applied smoothly in any thickness. This epoxy has a working life of 45 to 55 minutes at ambient temperature for a 200g batch, and cures at room temperature or faster at elevated temperatures. It bonds well to a wide variety of substrates, including metals, glass, ceramics, cements, vulcanized rubbers, wood and many plastics.

EP21AR is packaged in pint, quart, gallon and five-gallon container kits. It is widely used in an array of industries, including oil and chemical processing, maintenance and repair, optics, metalworking, appliance, and electrical/electronic.