Dow 839 Silicone Adhesive/Sealant

Dow 839 Silicone Adhesive/Sealant Datasheet
  • Description for Dow 839 Silicone Adhesive/Sealant

    Silicone adhesive sealant one-part, translucent blue, moisture cure adhesives are generally cured at room temperature, non-flowing, automated or manual needle dispensing systems.

    *See Terms of Use Below

    Application Type Bond, Seal, Gaskets
    1 Part or 2 Part 1 Part
    Material Form Liquid, Silicone elastomer
    Substrate Ceramics, Glass, Reactive metals, Plastics, Resins
    Industry Circuit boards, Light Emitting Diodes (LEDs), Smart Meters, E-Mobility Solutions, Smart Home Devices, CRT module, Electrical leads, Electronic equipment, Electronics, LCD module, Modules, PDP module, Power supplies, PWBs
    Manufacturer Dow
    Chemistry Silicone elastomer
    Cure Method RTV, Moisture
    Cure Temperature (°C) 20 to 25
    Cure Time (min) 2,880
    Viscosity (cPs) Non-flow
    Color Blue, Translucent
    High Temperature Resistance (°C) 200
    Low Temperature Resistance (°C) -45, -55
    Extrusion Rate 179 (g/min)
  • Technical Data for Dow 839 Silicone Adhesive/Sealant

    Overview
    • Application Type
    • 1 Part or 2 Part
      • 1 Part or 2 Part - 1 Part
    • Material Form
      • Elastomer - Silicone elastomer
      • Liquid
    • Substrate
    • Industry
      • LED (Light-Emitting Diodes) - Light Emitting Diodes (LEDs)
      • E-Mobility Solutions
      • Electronics - Circuit boards, CRT module, Electrical leads, Electronic equipment, LCD module, Modules, PDP module, Power supplies, PWBs
      • Smart Meters
      • Smart Home Devices
      • Power Supplies
      • Industrial - Housings, Yoke
    • Chemistry
    • Application Method
      • Dispenser - Automated or manual needle dispensing systems
    • Cure Method
      • Moisture / Condensation Cure - Moisture
      • RTV (Room Temperature Vulcanization) - RTV
    • Color
      • Translucent - Translucent
      • Blue
    Specifications
    Cure Specs
    Cure Temperature (°C) 20 to 25
    Cure Time (min) 2,880
    Viscosity (cPs) Non-flow
    Tack Free Time (min) 35 Test Method
    Bond Strength
    Peel Strength (piw) 25.5 (N/cm2)
    Shear Strength (psi) 140 Test Method
    Tensile Strength (psi) 285
    Material Resistance
    Environmental Resistance Environmental resistance
    High Temperature Resistance (°C) 200
    Low Temperature Resistance (°C) -45, -55
    Moisture/Humidity Resistance Moisture/humidity resistance
    Conductivity
    Dissipation Factor 0.00090, <0.00020 Test Method
    Dielectric Strength (V/mil) Good, 480 Durable, 19 (kV/mm)
    Dielectric Constant 2.51, 2.49 Test Method
    Volume Resistivity (O) 2.5E+14 (ohms/cm)
    Hardness
    Shore A Hardness 32
    Elongation (%) 345
    Flexibility Flexible
    Other Properties
    Extrusion Rate 179 (g/min)
    Specific Gravity 1.020
    Coefficient of Thermal Expansion (CTE) 300 (Linear (micron/m °C or ppm ))
    Business Information
    Shelf Life Details Shelf life is indicated by the “Use Before” date found on the product label. For best results, Dow Corning RTV adhesives should be stored at or below 25°C (77°F). Special precautions must be taken to prevent moisture from contacting these materials. Containers should be kept tightly closed with head or air space minimized. Partially filled containers should be purged with dry air or other gases, such as nitrogen.
    Shelf Life Temperature (°F) <90
    Shelf Life Type from date of manufacture
    Shelf Life (mon) 24
    Not Good For
    Don't Use With Plastic, rubber
  • Best Practices for Dow 839 Silicone Adhesive/Sealant

    *See Terms of Use Below

    1. Surface Preparation

      All surfaces should be thoroughly cleaned and/or degreased with Dow Corning® brand OS Fluids, naphtha, mineral spirits, methyl ethyl ketone (MEK) or other suitable solvent. Solvents such as acetone or isopropyl alcohol (IPA) do not tend to remove oils well, and any oils remaining on the surface may interfere with adhesion. Light surface abrasion is recommended whenever possible, because it promotes good cleaning and increases the surface area for bonding. A final surface wipe with acetone or IPA is also useful. Some cleaning techniques may provide better results than others

      users should determine the best techniques for their particular applications.

    2. Mixing

      Upon standing, some filler may settle to the bottom of the liquid containers after several weeks. To ensure a uniform product mix, the material in each container should be thoroughly mixed prior to use. Two-part materials should be mixed in the proper ratio (1:1 or 10:1) either by weight or volume. The presence of light colored streaks or marbling indicates inadequate mixing.

    3. Deairing/Degassing

      Automated airless dispense equipment can be used to reduce or avoid the need to de-air. If de-airing is required to reduce voids in the cured elastomer, consider a vacuum de-air schedule of >28 inches Hg for 10 minutes or until bubbling subsides.

  • Comparable Materials for Dow 839 Silicone Adhesive/Sealant

    *See Terms of Use Below

    Spec Engine® Results

Questions about this material?

Get personal assistance with your specific application needs.

Your Profile Edit
  1. 1aee03a5-3b02-4563-bfb2-5bf62f102a0f
  2. 1aee03a5-3b02-4563-bfb2-5bf62f102a0f

Popular Articles

Testing the effectiveness of surface treatments

Read Article

Infographic: ENSURING A STRONG BOND - 6 Basic Methods of Surface Preparation

Read Article

What Are the Differences Between Adhesives and Sealants?

Read Article

Silicones in LED Lighting | Gluespec

Read Article

Sponsored Articles

Unique Advantages of Contact Adhesives

Read Article

Using LOCTITE® 454™ is a Valid Option for Engineers Working with a Wide Variety of Materials

Read Article

Sylgard 184 by DOW is the Top Choice for a Transparent, Silicone Encapsulant. Read Why:

Read Article

Case Study: Creating reliable, corrosion-free bonds with LORD® 406 acrylic adhesive

Read Article
Information provided by Gluespec

Why Register?

  • View Technical Details
  • View Test Methods
  • View Key Specifications
  • View Similar Materials
  • Save your Project Searches

Already registered? Sign in.

Questions? Learn more about Gluespec

Gluespec Poll

When you're researching or sourcing materials online, what device are you using?
Tack Free Time Test Methods
Tack Free Time Tack Free Temperature
35 min 25°C
Shear Strength Test Methods
Shear Strength Type
140 psi Lap shear strength
Dielectric Constant Test Methods
Dielectric Constant Test Method
2.51 Dielectric constant, 100 Hz
2.49 Dielectric constant, 100 KHz
Dissipation Factor Test Methods
Dissipation Factor Test Method
0.00090 Dissipation factor, 100 Hz
<0.00020 Dissipation factor, 100 KHz