DOWSIL 839
Harmonization Code : 3919.10.80 | Other self-adhesive plastic rolls not exceeding 20 cm wide.
Main features
- One-Part No-Mix Sealing
- Non-Sag Placement Control
- Electronics Assembly and Module Sealing
Product Description
DOWSIL™ 839 Silicone Adhesive/Sealant is a one-part, translucent blue, non-flowing silicone adhesive and sealant for general-purpose electrical and electronic assembly. The moisture-cure material requires no mixing and cures at room temperature, with mild heat below 60°C (140°F) available to accelerate cure when appropriate. Its non-flowing consistency supports controlled application through automated or manual needle-dispensing systems. The product is suitable for sealing openings in modules and housings, stabilizing individual components, assembling components on printed wiring boards, and sealing around wired or electrical leads.
Key features
- One-part moisture-cure system: Requires no mixing and cures at room temperature in the presence of atmospheric moisture.
- Non-flowing consistency: Provides zero reported slump for controlled placement on components, modules, and housings.
- Dispensing flexibility: Can be applied using automated or manual needle-dispensing systems.
Applications / Suitable for
- Sealing openings in modules and housings
- Adding mechanical stability to individual components
- Assembly of components on printed wiring boards
- Sealing in and around wired and electrical leads
- Yoke assembly
TDS, SDS & Technical Documents
Technical Specifications
Physical Properties
Mechanical Properties
Additional Information
As-supplied / before-processing properties
Typical values are not intended for use in preparing specifications.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance and form | Translucent blue, non-flowing adhesive | — | One-part moisture-cure material |
| Extrusion rate | 179 | g/min | Test method and dispensing conditions not stated |
| Flow rate – slump | 0 | in / cm | Reported in both inch and centimetre units |
| Tack-free time | 35 | minutes | At 25°C |
After-processing / final-state properties
Typical cured-property values are not intended for use in preparing specifications. Cure and specimen conditions were not stated in the source table.
| Property | Value | Unit |
|---|---|---|
| Tensile strength | 285 / 2 / 20 | psi / MPa / kg/cm² |
| Durometer hardness | 32 | Shore A |
| Unprimed adhesion | 37 | ppi |
| Peel strength | 25.5 | N/cm² |
