Two component, epoxy polysulfide for bonding, sealing, coating and encapsulation

Key Features

  • Convenient handling
  • Tough, flexible bonds
  • Superior electrical insulation properties
  • Chemical resistance to fuels, oils, hydrocarbons and hydraulic fluids

Product Description

Master Bond EP21TPHT is a two component epoxy polysulfide system featuring easy processing. It has a one to one mix ratio by weight or volume. Mixing is straightforward as both Parts A and B are liquids. EP21TPHT cures readily at ambient temperatures in 48 to 72 hours. The optimum cure is overnight at room temperature followed by 2-3 hours at 150°F. The system has low shrinkage upon curing.

EP21TPHT bonds well to a variety of substrates, including metals, glass, ceramics and many rubbers and plastics. It is a toughened system with good elongation and flexibility. EP21TPHT can withstand rigorous thermal cycling as well as mechanical and thermal shock. The forte of the cured system is chemical resistance to water, gasoline, fuels, oils, hydrocarbons, hydraulic fluids, and lubricants.

This material is an outstanding electrical insulator. Also significant is that it has enhanced temperature resistance when compared to other epoxy polysulfide systems. The service temperature range is -80°F to +350°F. Part A is clear and Part B is slightly amber, although other colors are available upon request.

Polysulfide epoxies are a special group of adhesives and sealants since they combine good toughness along with chemical resistance. EP21TPHT should be considered in aerospace, electronic, electrical, specialty OEM, and other applications where the combination of chemical resistance, along with a measure of resiliency are desirable.

Product Advantages

  • Convenient mixing, forgiving 1:1 mix ratio by weight or volume
  • Brushable, easy to apply
  • Produces tough bonds that withstand thermal cycling
  • Good hardness and elongation
  • Exceptional resistance to fuels, oils, and similar chemicals

Industrial Certifications

Meets EU Directive 2015/863



Double Barrel Cartridge

Gun Applicator


EP21TPHT is available is various sizes and units to accommodate customer's needs.

Visual Media

Master Bond EP21TPHT is an epoxy polysulfide compound that withstands temperatures up to 350°F - giving it a higher resistance to elevated temperatures than most polysulfide systems.

Request Information