Two component, epoxy for high performance potting, encapsulation, sealing and bonding

Key Features

  • Superb optical clarity
  • Low viscosity
  • Highly flexible
  • Exceptionally long working life
  • Low exotherm during cure
  • Cures at room temperature

Product Description

Master Bond EP37-3FLSP is a low viscosity, optically clear, two component epoxy system featuring extraordinary flexibility. It fully cures in 7-10 days at room temperature and it can be accelerated by heat. The optimum cure schedule is 12-24 hours at room temperature, followed by 6-10 hours at 135-165°F. It generates very little heat while curing and has a decidedly long open time. It has a very forgiving two to one mix ratio by weight or volume. When used as an adhesive, it forms unusually flexible, high strength bonds that offer excellent impact resistance as well as the capability of withstanding severe thermal cycling and shocks. It bonds well to a wide variety of substrates including metals, composites, glass, ceramics, rubber and many plastics. Also, it offers good chemical resistance to water, oils and fuels. EP37-3FLSP is a superb system for potting and encapsulation, particularly for larger castings. It can easily be used in encapsulations up to and exceeding 1,000 grams. It has sound electrical insulation properties, noted below. Also, the lower exotherm while curing along with the Shore A hardness of 70 helps prevent EP37-3FLSP from causing stress on to electrical components during and after curing. EP37-3FLSP has been used in cryogenic applications and is serviceable from 4K to +200°F. Unlike many flexibilized systems, EP37-3FLSP has superior dimensional stability. This highly unique system can be used in aerospace, optical, electronic, electrical and OEM type applications where this distinctive blend of handling characteristics and cured properties is desirable.

Industrial Certifications

Meets EU Directive 2015/863




Gun Applicator


Premixed & Frozen Syringe

EP37-3FLSP is available is various sizes and units to accommodate customer's needs.

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