LOCTITE CAT 27-1
Harmonization Code : 8529.90 | Parts solely or principally used for TV, radio, and transmission

Main features
- Low-CTE Cured Epoxy
- Two-Hour Working Time
- Chemical-Resistant Cured Epoxy
Product Description
LOCTITE® CAT 27-1 is a high-performance epoxy hardener designed for use with LOCTITE STYCAST® 2850 MT encapsulation systems. The catalyst is engineered for applications requiring high thermal conductivity, excellent electrical insulation, low coefficient of thermal expansion (CTE), and outstanding thermal shock resistance. It is particularly suitable for high-voltage electronic assemblies, power devices, and encapsulation applications where heat dissipation and long-term reliability under elevated temperatures are critical.
Key Features & Benefits
- High thermal conductivity for effective heat dissipation.
- Excellent electrical insulation properties.
- Low coefficient of thermal expansion (CTE).
- Long working life and processing window.
- Excellent chemical resistance.
- Designed for high-voltage encapsulation and thermal shock environments.
- Maintains performance at elevated temperatures.
Recommended Applications
- Electronic component encapsulation.
- Power electronics and heat-generating assemblies.
- High-voltage insulation systems.
- Thermally conductive potting compounds.
- Industrial electrical equipment requiring thermal shock resistance.
TDS, SDS & Technical Documents
Technical Specifications
No specifications available.
Additional Information
As-Supplied / Before-Processing Properties
| Property | Value | Unit | Condition |
|---|---|---|---|
| Product Type | Epoxy Hardener | — | LOCTITE CAT 27-1 |
| Appearance | Brown Liquid | — | As supplied |
| Odor | Amine-like | — | Typical |
| Density | 1.05 | g/cm³ | 25°C |
| Viscosity | 300 | mPa·s (cP) | 25°C |
| Mix Ratio | 100 : 5 | Resin : Hardener | By weight |
| Working Time | 2 | hours | 100 g mass at 25°C |
| Flash Point | >100 | °C | SDS value |
After-Processing / Final-State Properties
| Property | Value | Unit | Condition / Method |
|---|---|---|---|
| Recommended Cure Schedule | 4 | hours | 120°C heat cure |
| Continuous Operating Temperature | -40 to +175 | °C | Typical service temperature |
| Intermittent Operating Temperature | -40 to +200 | °C | Typical service temperature |
| Thermal Conductivity | 1.6 | W/m·K | Cured system |
| Hardness | 94 | Shore D | Fully cured |
| Glass Transition Temperature (DMA) | 98 | °C | Tan δ maximum |
| Surface Resistivity | 1.7 × 10¹⁶ | Ω | Electrical property |
| Volume Resistivity | 4.5 × 10¹⁵ | Ω·cm | Electrical property |
| Linear Shrinkage | 0.52 | % | Cured material |
| Water Absorption (7 Days) | 0.09 | % | Room temperature |





















