Two component, low viscosity epoxy polysulfide for bonding, sealing, coating and casting

Key Features

  • Outstanding chemical resistance
  • High flexibility
  • Electrically insulative
  • Cures at room temperature
  • Serviceable from -65°F to +250°F
  • Suitable for bonding, sealing, coating, encapsulation and casting

Product Description

Master Bond EP21TPFL-1 is a two component, low viscosity epoxy polysulfide system, which upon curing, offers a highly special combination of flexibility and chemical resistance. EP21TPFL-1 has excellent resistance to a wide array of chemicals including water, gasoline, fuels, oils, hydrocarbons and hydraulic fluids. It has been formulated to cure readily at ambient temperatures. Unlike most two part epoxies, heat curing is not recommended. This system has a non-critical mix ratio of one to two, by weight or volume. EP21TPFL-1 has good physical strength and superior electrical insulation properties. This allows the system to be utilized in situations involving rigorous thermal cycling as well as thermal and mechanical shocks. It has very good adhesion to metals, ceramics, glass, and many rubbers and plastics. Since it is a first class insulator, with low viscosity as well as low exotherm, it is serviceable as a potting and encapsulation system. The service temperature range is -60°F to +250°F. The color of Part A is clear while Part B is brown. Polysulfide systems have been traditionally used for many years as fuel tank sealants, as well as for electrical connectors exposed to fuels, oils and lubricants, for many years. EP21TPFL-1 can also be used in aerospace, electronic and specialty OEM, among other applications, where this highly unusual combination of superb flexibility along with superior chemical resistance is desirable.

Product Advantages

  • Convenient mixing: forgiving one to two mix ratio by weight or volume
  • Low viscosity enhances ease of application, compound flows evenly and smoothly; ideal for potting
  • Cures at ambient temperatures
  • 100% reactive — no volatiles emitted during curing
  • Outstanding flexibility with superior resistance to thermal cycling
  • Polysulfide type chemical resistance profile



Double Barrel Cartridge


Gun Applicator



EP21TPFL-1 is available is various sizes and units to accommodate customer's needs.

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