Master Bond EP21ARLV is a two part epoxy that may be used as an adhesive, sealant, coating or encapsulant. The product is capable of withstanding prolonged exposure to a wide range of chemicals, such as 70% sulfuric acid, 10% hydrochloric acid, 10% nitric acid and butyl acetate to name a few. Both parts A and B have a low viscosity of 3,000-6,000 cps and 4,000-6,000 cps, respectively. “With its low viscosity and acid resistance, EP21ARLV is a go-to material for potting and encapsulations in battery applications,” says Rohit Ramnath, Senior Product Engineer. “This combination is especially useful in applications where protection from acids is crucial.” 

The mix ratio of EP21ARLV is 100 to 50 by weight, and it cures at room temperature. However, the addition of heat not only speeds up the curing process but it is also vital for optimizing acid resistance. It is a reliable electrical insulator with a volume resistivity greater than 10¹⁴ ohm-cm at 75°F, and dielectric strength of 440 volts/mil at 75°F, for a 1/8 inch test sample. Other noteworthy properties include a tensile strength of 8,000-9,000 psi, a Shore D hardness of 80-90 and a tensile modulus of 350,000-400,000 psi. It is serviceable over the temperature range of -60°F to +250°F.

This compound bonds well to a variety of substrates including metals, ceramics, composites and many plastics and rubbers. It is available for use in ½ pint, pint, quart and gallon container kits. Specialty packaging is also available in gun dispensers. The standard color of Part A is clear and Part B is amber clear, although it can be formulated in many different colors upon request. EP21ARLV does not contain solvents and is RoHS compliant.