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Cosmic Epoxy E4940S

1 of 25 products in this brand
Cosmic Epoxy E4940S is a mineral-filled epoxy molding compound supplied in granular form. It offers excellent dimensional stability, improved thermal cycling properties, and exceptional moisture resistance. This product is specifically designed for high-volume encapsulation of resistor networks and fiber-optic connectors that demand high quality, reliability, and excellent moldability.

Polymer Name: Epoxy Resins & Compounds

End Uses: Encapsulant, Optical Fiber Connector, Resistor Network

Volume Resistivity: 10000000000000.0 - 10000000000000.0 Ohm-m

Flexural Strength: 103.35 - 103.35 MPa

Knowde Enhanced TDS

Identification & Functionality

Fillers Included
Plastics & Elastomers Functions
Technologies

Features & Benefits

Key Features
  • It has excellent dimensional stability, improved thermal cycling and exceptional moisture resistance.
  • Standard spiral flow range is 25-35” (EMMI) at 1500C and 1000 psi.
  • It has a hot plate gel time of 22-30 seconds at 1600C, and 18-26 seconds at 1820C

Applications & Uses

Product Applications

It is designed for use in high-volume encapsulation of resistor networks and fiber-optic connectors requiring high quality, reliability and good moldability.

Properties

Flame Rating
Physical Form
Flame Rating
UL 94 V0
Mechanical Properties
ValueUnitsTest Method / Conditions
Flexural Strength15000psi
Flexural Modulus2.0 x 10⁶psi
Compressive Strength28000psi
Tensile Strength12000psi
Impact Strength (Izod Notched)0.5ft-lb / inch
Barcol Hardness65
Thermal Properties
ValueUnitsTest Method / Conditions
Heat Deflection Temperature260°C
Glass Transition Temperature (Tg)175°C
Coefficient of Linear Expansion (Alpha 1)20 x 10⁻⁶°C
Coefficient of Linear Expansion (Alpha 2)70 x 10⁻⁶°C
Thermal Conductivity16 x 10⁻⁴cal/sec/cm²/°C/cm
Electrical Properties
ValueUnitsTest Method / Conditions
Arc Resistance180seconds
Volume Resistance1 x 10¹⁵Ohm - cm
Surface Resistance1 x 10¹⁵Ohm - cm
Dielectric Strength (Kv Step-by-Step, Wet)350volts/mil
Dielectric Breakdown (Step-by-Step, Wet)56Kv
Dielectric Constant (at 1 KHz, Wet)3.9
Dissipation Factor (at 1KHz, Wet)0.012
Dielectric Constant (at 1 MHz, Wet)4.3
Dissipation Factor (at 1MHz, Wet)0.011
Moisture Properties
ValueUnitsTest Method / Conditions
Water Absorption (at 50 °C,48 hours)0.25%
Processing Information (Molding)
ValueUnitsTest Method / Conditions
Specific Gravity1.85
Bulk Factor2 - 5
Molding Pressure500 - 8,000psi
Molding Temperature150 - 180°C
Mold Shrinkage0.002 - 0.004In / In

Regulatory & Compliance

Certifications & Compliance

Storage & Handling

Shelf Life
6 months
Shelf Life Conditions

It has a shelf life of 6 months when stored at 5°C.