CONATHANE EN-7
Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other
Main features
- Fixed En-4 Plus En-7 System
- 30-Minute Gel Window
- Multiple Cure Schedule Options
Product Description
CONATHANE EN-4 / EN-7 is the curative in the fixed EN-4 Part A plus EN-7 Part B polyurethane system. EN-4 Part A is supplied separately and is always required for system use. The mixed and cured values shown apply only to this fixed pair and do not describe EN-7 Part B by itself or a prepacked kit. Documented applications include cables and connectors, modules and wound devices, and printed-circuit coatings. Cure options are 10 to 14 days at 25 C, 16 hours at 60 C, 8 to 10 hours at 80 C, or 4 to 6 hours at 100 C.
Key features
- Material system: Fixed EN-4 plus EN-7 system.
- Processing window: 30-minute typical gel time.
- System options: Multiple cure schedule options.
Applications
- Cables and connectors
- Modules and wound devices
- Printed-circuit coatings
Technical Specifications
General Properties
Thermal Properties
Additional Information
Potting, encapsulants and underfills
CONATHANE® EN-7 Curative for the EN-4 polyurethane system
CONATHANE® EN-7 is the Part B Curative used with CONATHANE® EN-4 Part A Urethane Prepolymer to form an unfilled, two-component, room-temperature-curing, 100%-solids polyurethane system. The complete EN-4 plus EN-7 system is used for electrical and electronic potting, molding, encapsulation, and selected coating applications. Mixed and cured values apply to the complete system and do not describe EN-7 Part B alone.
Technical properties
EN-7 Part B as-supplied properties
These values describe EN-7 Part B before mixing with EN-4 Part A.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance | Amber | Not applicable | As supplied |
| Viscosity | 1,000 | cP | 25°C / 77°F |
| Specific gravity | 1.00 | Unitless | 25°C / 77°F |
| Flash point | >94 / >201 | °C / °F | ASTM D93 |
EN-4 plus EN-7 system
Mix ratio and mixed-material properties
| Property | Condition | Typical value | Unit |
|---|---|---|---|
| Mix ratio EN-4 : EN-7 | By weight | 100:17.5 | Parts |
| Mix ratio EN-4 : EN-7 | By volume | 100:17 | Parts |
| Initial mixed viscosity | 25°C / 77°F | 5,500 | cP |
| Gel time | 25°C / 77°F | 30 | min |
| Peak exotherm | 2 lb mass at 25°C / 77°F | 55 / 130 | °C / °F |
Processing
Mix, degas, cure, and demold
Prepare and combine
Mix individual components before combining. Mix 100 parts EN-4 Part A with 17.5 parts EN-7 Part B by weight, or 100:17 by volume, until homogeneous.
Preheat and degas
Components may be preheated up to 60°C when reduced viscosity is required. For hand mixing, degas the mixed material at greater than 27 in. Hg vacuum before use.
Application methods
Supported methods include hand-mix bench potting or casting, meter-mix bench potting or casting, and meter-mix vacuum potting or casting.
| Stage | Temperature | Time |
|---|---|---|
| Cure | 25°C / 77°F | 10 to 14 d |
| Cure | 60°C / 140°F | 16 h |
| Cure | 80°C / 176°F | 8 to 10 h |
| Cure | 100°C / 212°F | 4 to 6 h |
| Demold | 25°C / 77°F | 8 h |
| Demold | 60°C / 140°F | 3 h |
Processing boundary: Cure timing begins after the unit reaches the specified temperature. Cure schedules are recommendations and should be evaluated for the actual application.
Cured EN-4 plus EN-7 system
Typical mechanical and environmental properties
| Property | Method | Condition | Typical value | Unit |
|---|---|---|---|---|
| Specific gravity | ASTM D792 | 25°C | 1.01 | Unitless |
| Shore hardness | ASTM D2240 | 25°C | A 90 | Shore A |
| Tensile strength | ASTM D412 | 25°C | >2,000 | psi |
| Ultimate elongation | ASTM D412 | 25°C | >400 | % |
| Tear strength | ASTM D624 | 25°C | >200 | pli |
| Linear shrinkage | MIL-M-24041C | Cured | 1.2 | % |
| Volumetric shrinkage | MIL-M-24041C | Cured | 3.7 | % |
| Water absorption | ASTM D570 | 24 h at 25°C | 0.2 | % |
| Water absorption | ASTM D570 | 30 d at 25°C | 0.4 | % |
| Thermal shock | MIL-I-16923E | -70°C to 130°C | Pass, 10 cycles | Result |
Electrical performance
Typical cured-system electrical properties
| Property | Method | Condition | Typical value | Unit |
|---|---|---|---|---|
| Dielectric strength | ASTM D149 | 1/16 in at 25°C | 780 | V/mil |
| Dielectric constant | ASTM D150 | 100 Hz / 1 kHz / 1 MHz at 25°C | 3.0 / 2.9 / 2.8 | Unitless |
| Dielectric constant | ASTM D150 | 100 Hz / 1 kHz / 1 MHz at 130°C | 3.8 / 3.8 / 3.3 | Unitless |
| Dissipation factor | ASTM D150 | 100 Hz / 1 kHz / 1 MHz at 25°C | 0.03 / 0.03 / 0.03 | Unitless |
| Volume resistivity | ASTM D257 | 25°C / 130°C | >4.3 x 1015 / 7.4 x 1011 | ohm-cm |
| Surface resistivity | ASTM D257 | 25°C / 130°C | >1.0 x 1015 / 1.6 x 1012 | ohms/sq. |
| Insulation resistance | MIL-M-24041C | 25°C / 130°C | >2.5 x 1013 / 2.3 x 1010 | ohms |
| Arc resistance | MIL-M-24041C | 25°C | >120 | seconds |
Hydrolytic stability
112-day exposure at 97°C / 95% RH
| Property | Original | After 112 days | Unit |
|---|---|---|---|
| Shore hardness | A 94 | A 87 | Shore A |
| Tensile strength | 2,250 | 1,750 | psi |
| Ultimate elongation | 400 | 370 | % |
| Tear strength, Die C | 320 | 190 | pli |
| Dielectric strength | 780 | 570 | V/mil |
| Volume resistivity | >4.2 x 1015 | 2.8 x 1015 | ohm-cm |
Data scope: Values are typical and are not intended for specification use.
Applications
Applications for the EN-4 plus EN-7 system
Cables and connectors
Potting and molding of military and commercial cables and connectors, watertight electrical connectors, harness breakouts, and cables.
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 the system components from moisture
Store at or below 25°C / 77°F in a dry controlled environment away from direct sunlight. The stated shelf life is 12 months from shipment in original sealed containers under the specified storage conditions.
The components are sensitive to moisture and atmospheric humidity. Protect opened material with dry air or nitrogen before resealing. If EN-4 Part A crystallizes during storage or shipment, heat to 60°C, mix thoroughly, and cool to room temperature before processing.
Discuss EN-7 with EN-4 Part A
Krayden can help evaluate the EN-4 plus EN-7 system around the required mixed viscosity, 30-minute gel time, cure schedule, demold target, electrical requirements, assembly geometry, and service environment.
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