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CoolTherm® SC-420 Thermally Conductive Silicone Encapsulant Contact Us to Buy

Product Information

LORD CoolTherm® SC-420 thermally conductive silicone encapsulant is a two-component system designed to provide excellent thermal conductivity and flexibility for electrical/electronic encapsulating applications, while retaining desirable properties associated with silicones.

Shelf Life

Shelf life of each component is nine months from date of manufacture when stored at 25°C in original, unopened container.

CoolTherm SC-420 hardener evolves minute quantities of hydrogen gas. Do not repackage or store material in unvented containers. Adequately ventilate work area to prevent the accumulation of gas.

Features and Benefits

Low Stress – exhibits low shrinkage and stress on components as it cures.

Durable – composed of an addition-curing polydimethyl siloxane polymer that will not depolymerize when heated in confined spaces.

Low Viscosity – maintains low viscosity for ease of component encapsulation compared to other highly thermally conductive materials.

Environmentally Resistant – provides excellent thermal shock resistance.

Uncured Typical Properties*

Mixed Appearance Gray Paste
Mixed Viscosity, cps @ 25°C 50,000
Mixed Specific Gravity 3.18
Gel Time, min @ 25°C 70
Working Life, min @ 25°C >30
Cure Time, min @ 125°C 60

Cured Typical Properties*

Volume Resistivity, ohm-cm @ 25°C 1 x 1014
Thermal Conductivity, W/mK 3.2
Coefficient of Linear Thermal Expansion, ppm/°C 100
Hardness, Shore A 20
Tensile Strength, psi 145
Elongation at Break, % 100
Moisture Absorption, % < 0.5
Dielectric Constant, @ 25°C < 5
Dissipation Factor, % @ 25°C < 1

* Data is typical and not to be used for specification purposes.
Cure schedule of 60 minutes at 125°C.


Download Type Name
Download Safety Data Sheet CoolTherm SC-420 Resin
Download Safety Data Sheet COOLTHERM SC-420 HARDENER
Download Technical Data Sheet CoolTherm SC-420 Thermally Conductive Silicone Encapsulant
Download Filled Addition-Curing Silicone Encapsulant Handling/Application Notes
Download Product Brochure/Bulletin/Sell Sheet Thermal Management Materials for the Oil & Gas Industry

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