Master Bond EP21LVFL is a two component, low viscosity epoxy system for bonding, sealing, coating, and encapsulation featuring excellent flexibility. It is easy to use, with a forgiving mix ratio of 1 to 2 by weight or volume. It has a long working life of 120-160 minutes. It cures readily at ambient temperature and more rapidly at elevated temperature, with the optimum cure being overnight at room temperature followed by 4-6 hours at 125-150°F. EP21LVFL has no solvents or diluents and very low shrinkage upon curing.
It is an excellent adhesive and bonds well to a wide range of substrates including metals, glass, ceramics, composites, as well as many types of rubbers and plastics. Its exceptionally high elongation allows it to withstand rigorous thermal cycling along with high vibration and shock. It is also notable for a very low tensile modulus. EP21LVFL is a reliable electrical insulator and these properties, combined with its low exotherm, allow it to be used for a variety of potting applications. The service temperature range is -100°F to +250°F. Part A is clear and Part B is amber clear, and it is available in many other colors, if needed. EP21LVFL can be used in electronics, aerospace, optical, and specialty OEM applications, among others, where the operating conditions require an adhesive that cures with good flexibility. The need for an epoxy with high elongation is even more pronounced when bonding substrates where there are different coefficients of thermal expansion. The compliant nature of this system also enhances its ability to resist thermal cycling, shock, vibration and other types of stresses.
