Master Bond EP21LVFL is a two-part epoxy said to combine good flexibility with a solid strength profile.
Curable at room temperature with a long working life of 120-160 min. at 75°F for a 100g batch and features a flowable initial mixed viscosity of 10,000-14,000cps. Generates low exotherm making it suitable not only for bonding and coating, but also for sealing and potting applications. Is said to be especially useful in bonding substrates with different coefficients of expansion such as metals, composites, glass, ceramics, rubbers and plastics. Has a high elongation of 120-150%, a low tensile modulus of 1,500-2,500 psi and a shore D hardness of 40-50. Features a volume resistivity exceeding 1015ohm-cm and a dielectric constant of 2.95 at 60Hz. Has a tensile strength of 1,200-1,400psi and a lap shear strength measuring 900-1,100psi. Is capable of withstanding rigorous thermal cycling, vibration, mechanical stress and shock. Offers a non-critical one to two mix ratio, by weight or volume. Part A is clear and Part B is amber clear, and can be formulated in other colors. Cures more rapidly at elevated temperatures, with optimal performance properties achieved by curing overnight at room temperature followed by 4-6 hrs. at 125-150°F.