COOLTHERM EP-6035
Harmonization Code : 3910.00.00.90 | Silicones in Primary Forms; Others
Main features
- 1.0 W/(m K) Thermal Encapsulation
- 12,000 cP Mixed Viscosity
- UL 94 V-0 Classification
Product Description
CoolTherm® EP-6035 Epoxy Encapsulant is a black, two-component epoxy system for thermally conductive potting, casting, and thin-bondline semiconductor attachment. The resin and hardener mix at a 1:1 ratio by weight or volume to form a 12,000 cP material with a typical two-hour working life at 25°C. It cures in 24 hours at 25°C or 2 hours at 65°C. Typical cured properties include 1.0 W/m·K thermal conductivity, 75 Shore D hardness, 18.7 kV/mm dielectric strength, and operation from -65°C to +155°C. The system is also identified as UL 94 V-0, subject to the exact listed formulation and test conditions.
Key features
- Low 12,000 cP mixed viscosity for potting, casting, and controlled thin-bondline application
- 1.0 W/m·K typical cured thermal conductivity
- 1:1 mix ratio by weight or volume for meter/mix/dispense processing
- Room-temperature or 65°C accelerated cure
- Typical dielectric strength of 18.7 kV/mm and volume resistivity of 1 × 1014 ohm-cm
- Low-exotherm room-temperature cure positioning
- Documented operating range from -65°C to +155°C
Applications
- Thermally conductive potting and casting
- Thin-bondline attachment of semiconductors to heat sinks
- Power electronics and electric-transportation assemblies requiring electrical isolation and heat transfer
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Thermal Properties
Mechanical Properties
Electrical Properties
Additional Information
CoolTherm® EP-6035 Epoxy Encapsulant
A black, two-component epoxy system for low-viscosity potting and casting and for thermally conductive thin-bondline attachment of semiconductors to heat sinks. EP-6035 combines a 1:1 mix ratio, two-hour working life, room-temperature or accelerated cure, and rigid cured electrical insulation for thermal-management assemblies.
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Component and mixed-material properties
The black resin and tan hardener form a black mixed material. Values below are typical and must not be treated as shipment specifications.
| Property | Black resin | Hardener | Mixed material |
|---|---|---|---|
| Appearance | Black liquid | Tan liquid | Black liquid |
| Viscosity at 25°C | 9,500 cP | 14,000 cP | 12,000 cP |
| Specific gravity | 1.62 | 1.57 | 1.57 |
| Working life at 25°C | 2 hours after mixing | ||
Premix both components, combine 1:1, control air, and cure
Thoroughly mix the resin and hardener separately before combining them at a 1:1 ratio by weight or volume. Mix the complete system without whipping excessive air into the material. Where entrapped air remains, evacuate the mixture before pouring or dispensing.
- Apply using validated automatic meter/mix/dispense equipment.
- Cure for 24 hours at 25°C or 2 hours at 65°C.
- Count cure time after the material reaches the stated temperature.
- Account for oven ramp, part thermal mass, cavity volume, and other factors that delay material temperature.
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Restore both resin and hardener to a uniform state before metering.
Use equal parts by weight or volume and maintain ratio accuracy.
Mix uniformly while minimising entrapped air; evacuate where required.
Apply within the two-hour working life and use the selected time-at-temperature cure.
Storage and handling
Each component has a one-year shelf life when stored at 25°C in its original, unopened container. Before handling, review the current resin and hardener safety data sheets and labels. The black resin is classified as an industrial epoxy resin and requires controls for skin and eye contact, sensitisation, ventilation, and environmental release.
Thermal, mechanical, and electrical properties
Values below are typical cured-material results. Thermal conductivity and dielectric data describe the tested bulk material and do not independently establish complete assembly thermal resistance, working voltage, or reliability.
| Property | Typical value | Context |
|---|---|---|
| Thermal conductivity | 1.0 W/m·K | Hot Disc Transient Method, ISO 22007-2. |
| Coefficient of linear thermal expansion | 35 ppm/°C | Bulk cured-material value. |
| Hardness | 75 Shore D | Rigid cured epoxy. |
| Tensile strength | 34.5 MPa (5,000 psi) | Bulk tensile specimen property. |
| Elongation at break | 5.0% | Bulk tensile specimen property. |
| Volume resistivity at 25°C | 1 × 1014 ohm-cm | ASTM D257. |
| Dielectric strength | 18.7 kV/mm (475 V/mil) | ASTM D149; not a working-voltage rating. |
| Dielectric constant | 4.1 at 100 Hz | ASTM D150. |
| Dissipation factor | 0.025 at 100 Hz | ASTM D150. |
Thermally conductive bonding, potting, and casting
EP-6035 has two directly supported functions: thin-bondline attachment of semiconductors to heat sinks and low-viscosity potting or casting where thermal conductivity, electrical insulation, and flame retardancy are required. Portfolio brochures also position it for evaluation in electric-transportation power electronics and motor-related assemblies.
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CoolTherm application brochures and potting catalogue
These non-TDS/SDS resources provide broader selection and application context. Their market-level statements should not be treated as EP-6035-specific qualification or system-performance evidence unless the resource identifies the product and test configuration directly.
Electric ATVs, UTVs and Snowmobiles — PB3114
Overview of CoolTherm materials for batteries, motors, power electronics, and recreational electric vehicles; lists EP-6035 in the potting portfolio.
Electric Forklifts — PB3112
Application-selection context for thermal materials used in electric forklift batteries, motors, chargers, and power electronics.
Electric Marine — PB3113
US-format overview of potting, adhesives, gap fillers, and coatings for electric marine thermal management; includes EP-6035 in the potting table.
Electric Marine — PB3113E
A4-format version of the electric marine CoolTherm materials overview for regional customer use.
Electric Motorcycles — PB3115
Portfolio context for thermal-management materials in electric motorcycle batteries, motors, charging systems, and power electronics.
Potting & Encapsulation Materials — PC3002
Portfolio comparison of Parker potting and encapsulation products, including EP-6035 chemistry, viscosity, mix ratio, cure, hardness, dielectric strength, and conductivity.
Evaluate EP-6035 for your thermal encapsulation or bondline
Krayden can help review potting geometry, semiconductor attachment, mix-ratio control, de-airing, dispensing, cure profile, bondline, exotherm, electrical isolation, flame requirements, and assembly-level thermal validation for CoolTherm® EP-6035.
