Master Bond EP41S-5 is a two part epoxy system for bonding, sealing, coating and encapsulating with what the company says is a forgiving 100 to 25 mix ratio by weight. EP41S-5 will cure at room temperature or more rapidly at elevated temperatures. The optimum curing schedule is overnight at 75°F followed by 3-4 hours at 150-200°F. It has exemplary resistance to a wide array of chemicals, especially acids, bases, alcohols, fuels and many solvents.
Most noteworthy is its resistance to methylene chloride, phenol (10%) and nitric acid (30%). Upon mixing, EP41S-5 is a moderate viscosity liquid with good flow. It contains no solvents or diluents and is 100% reactive. It has low shrinkage upon curing. This epoxy combines formidable physical strength properties and electrical insulation values. It bonds well to a wide variety of substrates including metals, composites, glass, ceramics, as well as many rubbers and plastics. EP41S-5 is serviceable over a wide temperature range of -80°F to +300°F. The natural color of EP41S-5 is black. Additional colors are also available. If required, a non-drip version of this formulation called EP41S-5ND is offered as well. This epoxy system can be used in aerospace, electronic, chemical processing, specialty OEM and in other applications where robust chemical resistance is required.