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EPO-TEK® 302-3M Transparent Epoxy, Room Temperature Cure (8oz)

ET302-3M-8OZ

EPO-TEK® 302-3M Optically Transparent Epoxy, Room Temperature Cure, 2-Part Fiber Optic Epoxy, 8oz Kit
The EPO-TEK® 302-3M Optically Transparent Epoxy is a two-component epoxy used for optical, fiber optic, and semiconductor applications. The epoxy is good for adhesive bonding, sealing, potting, or as a coating. Recommended Cure: 65°C (149°F) for 3 Hours. Available in an 8oz kit.

Features:

  • Low-viscosity, colorless, clear epoxy well-suited for potting and for transmitting VIS or NIR light in opto-circuits
  • Excellent resistance to water, chemicals, and solvents such as 10% nitric acid, acetone, hexane, and dichloromethane
  • Passes NASA low outgassing standard ASTM E595 with proper cure
  • Pot life: 1 Hour

Applications:

  • Fiber Optic / Optical:
    • Potting and encapsulation; lens and prism bonding for scientific/OEM instruments; LED encapsulation
    • VIS/NIR transmission from 350–1550 nm; suitable for use directly in the optical pathway
    • Potting or sealing fibers into the snout of opto-packages
    • Adhesive for V-grooves, fiber arrays, or lens arrays
    • Bonding optical fibers into ferrules (glass or plastic fibers; ferrules made of glass, quartz, stainless steel, Kovar, or ceramic)
  • Semiconductor:
    • Recommended for underfilling flip chips or SMDs on PCBs
    • Suitable for COB glob-top processes using a DAM/FILL method
    • Resistant to 85/85 moisture soaks, thermal cycles, and thermal shock

Physical Properties:

  • Consistency: Pourable liquid
  • Viscosity (23°C) @ 100 rpm: 800 - 1,600 cPs
  • Glass Transition Temperature, Tg: ≥ 55°C (degree Celsius); ≥ 131°F (degree Fahrenheit)
  • Shore D Hardness: 80
  • Coefficient of Thermal Expansion (CTE):
    • Below Tg: 56 x 10-6 in/in°C
    • Above Tg: 193 x 10-6 in/in°C
  • Suggested Operating Temperature: < 250 °C (Intermittent); < 482°F

Optical Properties:

  • Spectral Transmission: > 95% @ 460-1620 nm
  • Refractive Index (uncured): 1.5446 @ 589 nm
See Datasheet for additional properties and application notes

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