CONATHANE EN-4
Harmonization Code : 3910.00.00.90 | Silicones in Primary Forms; Others
Main features
- Urethane Prepolymer Part A
- 9,000 cP Component Viscosity
- Compatible Curative Flexibility
Product Description
CONATHANE EN-4 Part A Urethane Prepolymer is the Part A component for two-component polyurethane potting, casting and molding systems. The amber liquid has a viscosity of 9,000 cP and a specific gravity of 0.97 at 25 deg C. It is used with an approved CONATHANE curative, such as EN-7 or EN-8, to create a complete system for electrical and electronic protection. The selected Part B controls the mix ratio, working life, cure schedule and final properties, so EN-4 Part A should not be evaluated as a complete encapsulant by itself.
Key features
- Urethane Prepolymer Component: provides Part A for compatible CONATHANE potting and molding systems
- 9,000 cP Viscosity: defines the component viscosity at 25 deg C
- Multiple Curative Options: works with approved Part B choices for different system requirements
Applications
Part A component for cable, connector, module, printed-circuit and wire-wound-device potting or molding systems.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Thermal Properties
Physical Properties
Electrical Properties
Mechanical Properties
Additional Information
Potting, encapsulants and underfills
CONATHANE® EN-4 Part A Urethane Prepolymer
CONATHANE® EN-4 is the Part A urethane prepolymer used with documented CONATHANE® Part B curatives to form two-component polyurethane potting, encapsulation, molding, and coating systems. Documented pairings include EN-7, EN-8, and EN-9 Curatives. The selected Part B establishes the mixed-material processing window, cure schedule, and final system properties, so EN-4 Part A should be evaluated together with the intended curative for the application.
Technical properties
EN-4 Part A as-supplied properties
These values describe EN-4 Part A before addition of a Part B curative. Mixed, processing, and final-state properties are system-specific.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance | Amber liquid | Not applicable | As supplied |
| Viscosity | 9,000 | cP | 25°C |
| Specific gravity | 0.97 | Unitless | 25°C |
| NCO content | 8.9 to 9.1 | % | As supplied |
| Shelf life | 15 | months | From date of manufacture in original sealed container |
System selection
Documented EN-4 curative pairings
EN-7, EN-8, and EN-9 are documented Part B curatives for EN-4 Part A. Each pairing uses the same stated 100:17.5 ratio by weight and 100:17 ratio by volume, but the mixed viscosity, gel behavior, and cure schedule differ by curative.
| Selection parameter | EN-4 + EN-7 | EN-4 + EN-8 | EN-4 + EN-9 |
|---|---|---|---|
| Part B curative | EN-7 | EN-8 | EN-9 |
| Part B viscosity at 25°C | 1,000 cP | 1,000 cP | 950 cP |
| Mix ratio by weight | 100:17.5 | 100:17.5 | 100:17.5 |
| Mix ratio by volume | 100:17 | 100:17 | 100:17 |
| Initial mixed viscosity at 25°C | 5,500 cP | 5,500 cP | 6,800 cP |
| Gel behavior at 25°C | 30 min gel time | 20 min gel time | 80 min to 100,000 cP; 120 min to 250,000 cP |
| Peak exotherm | 55°C, 2 lb mass at 25°C | 55°C, 2 lb mass at 25°C | 55°C, 2 lb mass at 25°C |
| Ambient cure | 10 to 14 d at 25°C | 5 to 7 d at 25°C | Not listed in stated cure schedule |
| Accelerated cure | 16 h at 60°C; 8 to 10 h at 80°C; 4 to 6 h at 100°C | 4 h at 60°C; 2 h at 80°C; 1 h at 100°C | 24 h at 60°C; 16 h at 80°C; 8 h at 100°C |
System boundary: Processing and cured-property values belong to the identified EN-4 plus curative combination. Do not transfer one curative system's values to another pairing.
Cured system comparison
Typical properties by curative pairing
The following data describe complete cured systems rather than EN-4 Part A alone.
| Property | EN-4 + EN-7 | EN-4 + EN-8 | EN-4 + EN-9 | Method / condition |
|---|---|---|---|---|
| Shore hardness | A 90 | A 90 | A 90 | ASTM D2240, 25°C |
| Tensile strength | >2,000 psi | >2,000 psi | 2,000 psi | ASTM D412, 25°C |
| Ultimate elongation | >400% | >400% | 450% | ASTM D412, 25°C |
| Tear strength | >200 pli | >200 pli | 280 pli | ASTM D624, 25°C |
| Water absorption | 0.2% | 0.2% | 0.2% | ASTM D570, 24 h at 25°C |
| Dielectric strength | 780 V/mil | 780 V/mil | 750 V/mil | ASTM D149, 1/16 in at 25°C |
| Thermal shock | Pass, 10 cycles | Pass, 10 cycles | Pass, 10 cycles | MIL-I-16923E, -70°C to 130°C |
Data scope: Values are typical and are not intended for specification use.
Applications
Applications for documented EN-4 systems
With the appropriate documented Part B curative, EN-4 systems are used for electrical and electronic potting, molding, encapsulation, and selected coating applications.
Cables and connectors
Potting and molding of electrical cables and connectors, including watertight connectors and harness breakouts.
Modules and wound devices
Potting and encapsulation of modules, wire-wound devices, and strain-sensitive components.
Printed circuitry
100%-solids and solvent-based coating applications for printed circuitry and components.
Storage and handling
Protect EN-4 Part A from moisture
Store EN-4 Part A below 25°C / 77°F in a dry controlled environment away from direct sunlight. Shelf life is 15 months from date of manufacture in the original sealed container under the stated storage conditions.
EN-4 Part A is sensitive to moisture and atmospheric humidity. Protect opened material with dry air or nitrogen before resealing. EN-4 Part A may crystallize during storage or shipment. If crystallization occurs, heat to 60°C, mix thoroughly, and cool to room temperature before processing.
Select the EN-4 system for your processing requirements
Krayden can help evaluate documented EN-4 curative combinations around mixed viscosity, working and gel behavior, cure temperature, demold target, electrical requirements, mechanical properties, assembly geometry, and service environment.
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