LOCTITE 383
Harmonization Code : 5906100000 | Adhesive tape of a width not exceeding 20cm
Main features
- High-Viscosity Placement Control
- 0.602 W/(m K) Thermal Bonding
- One-Component Thermal Bonding System
Product Description
LOCTITE® 383 is a one-component, thermally conductive modified acrylic adhesive designed for bonding heat-generating electronic components to heat sinks and printed circuit board assemblies. The grey, high-viscosity paste provides excellent heat dissipation through its enhanced thermal conductivity while delivering high structural strength after cure. Used with a compatible activator, LOCTITE 383 cures at room temperature, enabling efficient assembly and service-friendly reworkability. Typical applications include bonding transformers, transistors and other heat-generating components where both thermal management and mechanical reliability are required.
Key Features & Benefits
- One-component modified acrylic adhesive.
- Thermally conductive formulation for efficient heat dissipation.
- Room-temperature cure with activator.
- High structural strength for electronic assemblies.
- Excellent bonding of heat-generating components to heat sinks.
- Controlled strength allows field and service repair.
- Suitable for thermally sensitive electronic applications.
Recommended Applications
- Bonding transformers to heat sinks.
- Attaching transistors and power devices.
- Electronic assembly thermal management applications.
- Printed circuit board assemblies requiring heat dissipation.
- Structural bonding of electronic components.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Specific Gravity
1.5
Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.
For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless.
Physical Properties
Viscosity
500,000 - 1,100,000 mPa.s
Viscosity is a measurement of a fluid’s resistance to flow.
Viscosity is commonly measured in centiPoise (cP). One cP is defined as
the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP.
A product like honey would have a much higher viscosity -around 10,000 cPs-
compared to water. As a result, honey would flow much slower out of a tipped glass than
water would.
The viscosity of a material can be decreased with an increase in temperature in
order to better suit an application
Young's modulus
1,600 MPa
Thermal Properties
Thermal Conductivity
0.602 W/m.K
Thermal conductivity describes the ability of a material to conduct heat. It is required by power packages in order to dissipate heat and maintain stable electrical performance.
Thermal conductivity units are [W/(m K)] in the SI system and [Btu/(hr ft °F)] in the Imperial system.
Mechanical Properties
Elongation
7.8 %
Elongation is the process of lengthening something.
It is a percentage that measures the initial, unstressed, length compared to the length of the material right before it breaks.
It is commonly referred to as Ultimate Elongation or Tensile Elongation at break.
Electrical Properties
Volume Resistivity
5.2×10^11 Ohms⋅cm
Volume resistivity, also called volume resistance, bulk resistance or bulk resistivity is a thickness dependent measurement of the resistivity of a material perpendicular to the plane of the surface.
Additional Information
Technical Properties
As-Supplied / Before-Processing Properties
| Property | Value | Unit | Condition |
|---|---|---|---|
| Technology | Modified Acrylic | — | Thermally conductive adhesive |
| Appearance | Grey Paste | — | Uncured |
| Components | One Component | — | No mixing required |
| Specific Gravity | 1.5 | — | 25°C |
| Viscosity | 500,000 - 1,100,000 | mPa·s | Brookfield HBT, 25°C |
| Cure Method | Activator Cure | — | Room-temperature cure |
| Strength Classification | High | — | Structural bonding |
Technical Properties
After-Processing / Final-State Properties
| Property | Value | Unit | Condition / Method |
|---|---|---|---|
| Thermal Conductivity | 0.602 | W/m·K | ISO 8302 |
| Coefficient of Thermal Expansion | 71 × 10⁻⁶ | K⁻¹ | ISO 11359-2 |
| Tensile Strength at Break | 16 | N/mm² | ISO 527-3 |
| Elongation at Break | 7.8 | % | ISO 527-3 |
| Young's Modulus | 1,600 | N/mm² | ISO 527-3 |
| Volume Resistivity | 5.2 × 10¹¹ | Ω·cm | IEC 60093 |
| Surface Resistivity | 8.6 × 10¹³ | Ω | IEC 60093 |
| Dielectric Breakdown Strength | 1.5 | kV/mm | IEC 60243-1 |
| Lap Shear Strength (Steel, 0.05 mm Gap) | ≥12.4 | N/mm² | ISO 4587 |
