RBC-3500 Resin

Electronics
, Potting & Encapsulating
4 hours
Pot Life
4,400
Mixed Viscosity (cps)
90
Hardness (Shore D)
-65 to 155
Operating Temperature Range (°C)

RBC-3500 is a medium viscosity, filled epoxy casting resin offering low shrinkage and good machineability. It can be cured at room temperature or elevated temperatures depending upon the epoxy hardener selected and the properties required. The epoxy resin itself can be warmed slightly before the addition of epoxy hardener to facilitate mixing. With proper hardener selection, #3500 epoxy resin can be used for very large as well as very small, intricate castings where good flowability and excellent air release are required.

HANDLING PROPERTIES:

Mixed Viscosity @ 25oC, cps: 4,400
Shelf Life, (closed Container @ 25oC): 12 months

PHYSICAL PROPERTIES (CURED):

Color: Black
Specific Gravity @ 25oC: 1.60
Hardness, Shore D: 90
Linear Shrinkage, in./in.: 0.002
Moisture Absorption 10 Days @ 25oC, %: 0.19
Izod Impact Strength, ft. lbs./in. of notch: 0.40
Tensile Strength @ 25oC, psi: 6,900
Compressive Strength @ 25oC, psi: 28,700

THERMAL PROPERTIES (CURED):

Thermal Conductivity, cal/sec/cm2/oC/cm X 10-4: 8.4
Thermal Stability, 1000 Hrs. @ 175oC, % Wt. Loss: 0.50
Coefficient of Thermal Expansion, in./in./oC X 10-6: 29
Heat Distortion Temperature, oC: 150
Operating Temperature Range, oC: -65 to 155

ELECTRICAL PROPERTIES (CURED):

Volume Resistivity @ 25oC, ohm-cm: 5×1016
Dielectric Strength, volts/mil: 475
Dielectric Constant @ 25oC, 100 KC: 3.90
Dissipation Factor @ 25oC, 100 KC: 0.018

(Note: The above properties are typical of a system cured with hardener #AB-312.) 

RECOMMENDED HARDENERS:

A-110: A rigid, room temperature curing system with limited pot life and fast cure.

A-120: A resilient, low viscosity system with slightly longer pot life, that exhibits excellent resistance to thermal shock.

AB-312: Good resistance to heat, chemicals, thermal and mechanical shock, and good electrical properties at high humidity.

MIXING INSTRUCTIONS:

Weigh the desired amount of #3500 Resin into a clean container and combine with recommended hardener in one of the ratios shown below.

Hardener Parts by Weight
per 100 pts. Resin
Pot Life 
100 grams @ 25oC
A-110 5.7 1 hour
A-120 12.2 2 hours
AB-312 13 4 hours

RECOMMENDED CURE SCHEDULE

Hardener Cure @ 25oC Cure @ 65oC Cure @ 100oC Cure @ 130oC
A-110 24 hours 2 hours
A-120 24 hours 2 hours
AB-312 6 hours 5 hours 3 hours