High Thermal Conductivity Epoxy Casting Compound
DESCRIPTION:
Polycast 280 is a low viscosity, highly filled, epoxy formulation which, in addition to having excellent electrical properties, has high thermal conductivity and low thermal expansion. PC-280 is available in a thixotropic version for dipping applications.
| PROPERTIES - UNCURED: |
Part A |
Part B (PC 90) |
Part B (PC 67) |
|
| Color, Visual |
Black |
Amber |
Brown |
|
| Viscosity, cps. |
100,000 |
400 |
500 |
ASTMD2393 |
| Specific Gravity |
2.30 |
1.0 |
1.0 |
|
| Mix Ratio (By Weight) |
|
100:5-6 |
100:7-8 |
|
| Mixed Viscosity, cps. |
|
75,000 |
75,000 |
ASTMD2393 |
| Pot Life @ 72o F, hours |
|
1 |
4 |
|
| Shelf Life @ 72o F, months |
|
12 |
12 |
|
|
PROPERTIES - CURED:
|
|
|
|
| Hardness Durometer (Shore D) |
91 |
92 |
ASTMD 2240 |
| Tensile Strength, psi |
8000 |
8500 |
ASTMD 638 |
| Tensile Elongation, % |
1 |
1 |
ASTMD 638 |
| Compressive Strength, psi |
16,500 |
19,000 |
ASTMD 695 |
| Flexural Strength, psi |
11,500 |
13,000 |
ASTMD 790 |
| Coefficient of Thermal Expansion (cm/cm/°C) |
40 x 10-6 |
24 x 10-6 |
|
| Heat Distortion Point |
150°C |
150°C |
|
| Dielectric Strength, volts/mil |
450 |
475 |
|
|
Dielectric Constant, 60 Hz
|
6.2 |
6.4 |
ASTMD 150 |
| Dissipation Factor, 60 Hz |
0.02 |
0.02 |
ASTMD 150 |
| Volume Resistivity, ohm-cm |
1.3 x 1015 |
5 x 1015 |
ASTMD 257 |
| Thermal Conductivity, BTU (in)/(hr)(ft2 )(°F) |
10 |
10 |
|
MIXING INSTRUCTIONS:
1. Premix P.C. 280 in the original container prior to use to insure any settled filler may be reincorporated. Warming PC 280 to 100°F facilitates ease of use.
2. Weigh out the required amount of P.C.280 Part A and the requisite Part B.
3. Mix thoroughly, scraping both sides and bottom of container.
4. Evacuate mixture at 29 in. Hg for 5-10 minutes (if desired).
5. Pour into mold or cavity.
CURE SCHEDULE:
PC-90 - Room Temp. - 24 hrs. or 2 hours at 150°F.
PC-67 - Overnight at 125°F; or 2 hours at 200o F; or 1 hour at 250oF
NOTE: For service temperature above 300°F, post cure 2-3 hours at 325-350°F.
