Dow Dowsil 3-4237 Dielectric Firm Gel

Dow Dowsil 3-4237 Dielectric Firm Gel Datasheet
  • Description for Dow Dowsil 3-4237 Dielectric Firm Gel

    Firm or tough, thermal/mechanical shock and vibration damping, primerless chemical adhesion at room temperature (except 3-4237 Dielectric Firm Gel, which requires heat to develop chemical adhesion), excellent dielectric properties, flexible cure schedule, reversion resistant, thick section cure, compatible with automated dispensing equipment, and physical and electrical stability over a wide temperature range.

    *See Terms of Use Below

    Brand Dowsil
    Application Type Coating, Potting, Encapsulating
    1 Part or 2 Part 2 Part
    Material Form Gel
    Industry Optoelectronics, Automotive application, Various PCB system assembly application, Smart Meters, E-Mobility Solutions, Smart Home Devices
    Manufacturer Dow
    Chemistry Silicone
    Cure Method 2-Part Cure, Heat, Room Temperature
    Cure Temperature (°C) 100, 125, 150
    Cure Time (min) 35, 12, 7
    Color Translucent green, Translucent green
    High Temperature Resistance (°C) 200
    Low Temperature Resistance (°C) -45, -55
    Durability Tough
    Light Refractive Index (RI) High
  • Technical Data for Dow Dowsil 3-4237 Dielectric Firm Gel

    Overview
    • Application Type
    • 1 Part or 2 Part
      • 1 Part or 2 Part - 2 Part
    • Material Form
      • Gel
    • Industry
      • Automotive - Automotive application
      • E-Mobility Solutions
      • Electronics - Optoelectronics
      • Printed Circuit Board (PCB) - Various PCB system assembly application
      • Smart Meters
      • Smart Home Devices
    • Chemistry
    • Application Method
      • Dispenser - Automated dispensing equipment
    • Cure Method
      • Room Temperature / Air Dry - Room Temperature
      • Heat
      • 2-Part Cure
    • Color
      • Translucent - Translucent green
      • Green - Translucent green
    • Brand
      • Dowsil
    Specifications
    Cure Specs
    Cure Temperature (°C) 100, 125, 150 Test Method
    Cure Time (min) 35, 12, 7 Test Method
    Work / Pot Time (min) Long, 12,960 Test Method
    Mix Ratio 1:1, 1:1 (by volume)
    Bond Strength
    Peel Strength (piw) 3 (ppi) Test Method
    Material Resistance
    High Temperature Resistance (°C) 200
    Low Temperature Resistance (°C) -45, -55
    Moisture/Humidity Resistance Moisture/humidity resistance
    Conductivity
    Dissipation Factor 0.00200, 0.00007 Test Method
    Dielectric Strength (V/mil) Excellent, 475
    Dielectric Constant 2.96, 2.96 Test Method
    Volume Resistivity (O) 9E+14 (ohm*cm)
    Hardness
    Durability Tough
    Shore OO Hardness 25
    Flexibility Firm, Resilient, Flexible
    Other Properties
    Light Refractive Index (RI) High
    Specific Gravity 0.980 Test Method
    Coefficient of Thermal Expansion (CTE) 325 (ppm/°C) Test Method
    Business Information
    Shelf Life Details Storage conditions and shelf life (“Use By” date) are indicated on the product label.
    Shelf Life Type from date of manufacture
    Shelf Life (mon) 12
    Not Good For
    Don't Use For Some solder flux residues, Organotin compounds, Unsaturated hydrocarbon plasitcizers, Organometallic compounds, Silicone rubber containing organotin catalyst, Sulfur, Polysulfides, Polysulfones, Other sulfur containing materials
  • Best Practices for Dow Dowsil 3-4237 Dielectric Firm Gel

    *See Terms of Use Below

    1. Mixing

      Some gels are supplied in bladder packs that avoid direct air contact with the liquid gel components, allowing use of air pressure over the pack in a pressure pot for dispensing. Do not apply air pressure directly to the liquid gel surface (without the bladder pack) as the gel can become supersaturated with air and bubbling can occur when the material is dispensed and cured. Use of bladder packs prevents bubbling, maintains cleanliness and avoids gel contamination. Gels can be dispensed manually or by using one of the available types of meter mix equipment. Typically, the two components are of matched viscosities and are readily mixed with static or dynamic mixers, with automated meter-mix normally used for high volume processes. For low-volume applications, manual weighing and simple hand mixing may be appropriate. Inaccurate proportioning or inadequate mixing may cause localized or widespread problems affecting the gel properties or cure characteristics.

    2. Deairing/Degassing

      If possible, the potential for entrapment and incorporation of gas (typically air) should be considered during design of the part and selection of a process to mix and dispense the gel. This is especially important with higherviscosity and faster-curing gels. Degassing at > 28 inches (10–20 mm) Hg vacuum may be necessary to ensure a void-free, protective layer.

    3. Curing

      Working time (or pot life) is the time required for the initial mixed viscosity to double at room temperature (RT).

      The cure reaction begins when Parts A and B are mixed. As the cure progresses, viscosity increases until the material becomes a soft gel. Cure conditions are shown in the typical properties table. Cure is defined as the time required for a specific gel to reach 90% of its final properties. Gels will reach a no-flow state prior to full cure. Addition-cure silicone gels may be room temperature and heat cure or exclusively heat cure. Adding heat accelerates the cure reaction. Additional time should be allowed for heating the part to near oven temperature. Cure schedules should be verified in each new application.

      Certain materials, chemicals, curing agents and plasticizers can inhibit the cure of addition cure gels. Most notable of these include: organotin and other organometallic compounds, silicone rubber containing organotin catalyst, sulfur, polysulfides, polysulfones or other sulfur containing materials, unsaturated hydrocarbon plasticizers, and some solder flux residues. If a substrate or material is questionable with respect to potentially causing inhibition of cure, it is recommended that a small scale compatibility test be run to ascertain suitability in a given application. The presence of liquid or uncured product at the interface between the questionable substrate and the cured gel indicates incompatibility and inhibition of cure.

    4. Testing

      If a substrate or material is questionable with respect to potentially causing inhibition of cure, a small-scale compatibility test should be run to ascertain suitability in a given application. The presence of liquid or uncured product at the interface between the questionable substrate and the cured gel indicates incompatibility and inhibition of cure. In certain situations, toughened gels may appear fully cured but have reduced or no adhesion. This may result from slight inhibition at the interface.

  • Comparable Materials for Dow Dowsil 3-4237 Dielectric Firm Gel

    *See Terms of Use Below

    Spec Engine® Results

Questions about this material?

Get personal assistance with your specific application needs.

Your Profile Edit
  1. b8eb4ddf-5f59-46a6-905a-829dc6dee8cc
  2. b8eb4ddf-5f59-46a6-905a-829dc6dee8cc

Popular Articles

Electrically Conductive Adhesives

Read Article

Silicones in LED Lighting | Gluespec

Read Article

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

Read Article

Testing the effectiveness of surface treatments

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?
Cure Temperature Test Methods
Cure Temperature Cure Time Test Method
100°C Heat Cure
125°C Heat Cure
150°C Heat Cure
Cure Time Test Methods
Cure Time Test Method
35 min Heat Cure
12 min Heat Cure
7 min Heat Cure
Work / Pot Time Test Methods
Work / Pot Time Test Method Temperature
Long
12,960 min Time to double initial viscosity initial mixed viscosity for two-part products at room temperature. This property is sometimes referred to as pot life. 20 to 25°C
Peel Strength Test Methods
Peel Strength Type Test Method
3 (ppi) 180 Degree Peel Strength Unprimed Adhesion
Dielectric Constant Test Methods
Dielectric Constant Test Method
2.96 100 Hz
2.96 100 kHz
Dissipation Factor Test Methods
Dissipation Factor Test Method
0.00200 100 Hz
0.00007 100 kHz
Coefficient of Thermal Expansion (CTE) Test Methods
Coefficient of Thermal Expansion (CTE) CTE Test Method
325 (ppm/°C) Linear CTE (by TMA)
Specific Gravity Test Methods
Specific Gravity Test Method
0.980 Cured