Cosmic Epoxy E4940S

Chemical Family: Epoxy & Epoxy Derivatives

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.

Properties

Physical Form: Granules
Solid

Product families

Plastics — Thermoset Resins

Epoxies

Other characteristics

Brand: Cosmic Epoxy
End Uses: Encapsulant, Optical Fiber Connector, Resistor Network
Polymer Name: Epoxy Resins & Compounds
Flexural Strength: 103.35 - 103.35 MPa
Volume Resistivity: 10000000000000.0 - 10000000000000.0 Ohm-m
Markets: Electrical & Electronics
Shelf LIfe: 6 months
Flame Rating: UL 94 V0
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
Technology: Plastics
Fillers Included: Mineral
Material Features: Consistent High Quality
Dimensional Stability
Excellent Moisture Resistance
Good Moldability
Good Thermal Stability
Low Odor
Applications: It is designed for use in high-volume encapsulation of resistor networks and fiber-optic connectors requiring high quality, reliability and good moldability.
Handling Conditions: It has a shelf life of 6 months when stored at 5°C.
Certifications and Compliance: ISO 9001
UL 94
Plastics and Elastomers End Uses: Encapsulant
Optical Fiber Connector
Resistor Network
Plastics and Elastomers Functions: Resin

Technical data

Table 1 of 5

6 rows

Characteristic	Value	Unit
Flexural Strength	15000	psi
Flexural Modulus	2.0 x 10⁶	psi
Compressive Strength	28000	psi
Tensile Strength	12000	psi
Impact Strength (Izod Notched)	0.5	ft-lb / inch
Barcol Hardness	65	—

Table 2 of 5

5 rows

Characteristic	Value	Unit
Heat Deflection Temperature	260	°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 Conductivity	16 x 10⁻⁴	cal/sec/cm²/°C/cm

Table 3 of 5

9 rows

Characteristic	Value	Unit
Arc Resistance	180	seconds
Volume Resistance	1 x 10¹⁵	Ohm - cm
Surface Resistance	1 x 10¹⁵	Ohm - cm
Dielectric Strength (Kv Step-by-Step, Wet)	350	volts/mil
Dielectric Breakdown (Step-by-Step, Wet)	56	Kv
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	—

Table 4 of 5

1 row

Characteristic	Value	Unit
Water Absorption (at 50 °C,48 hours)	0.25	%

Table 5 of 5