High Thermal Conductivity Epoxy Casting Compound


Polycast 282 is a lower viscosity, highly filled, epoxy formulation. It has excellent electrical properties, and low thermal expansion. PC 282 is unique in that its high thermal conductivity results from different particle sized fillers.

PROPERTIES - UNCURED: Part A  Part B (PC 90) Part B (PC 67)  
Color, Visual Black  Amber   Brown  
Viscosity, cps. 150,000 400  500  ASTMD2393
Specific Gravity 2.60  1.0 1.0  
Mix Ratio (By Weight)    100:5-6  100:7-8  
Mixed Viscosity, cps.    60,000  60,000 ASTMD2393
Pot Life @ 72o F, hours   1 4  
Shelf Life @ 72o F, months   12 12  



Hardness Durometer (Shore D)   92 95 ASTMD 2240
Tensile Strength, psi   8000 8500 ASTMD 638
Tensile Elongation, %   1 1 ASTMD 638
Compressive Strength, psi   19,000 25,000 ASTMD 695
Flexural Strength, psi    11,500 13,000 ASTMD 790
Coefficient of Thermal Expansion (cm/cm/°C) 28 x 10-6   24 x 10-6  
Heat Distortion Point   155°C  190°C  
Dielectric Strength, volts/mil   400 400 ASTMD 149
Dielectric Constant, 60 Hz   6.1   6.3 ASTMD 150
Dissipation Factor, 60 Hz   0.02 0.02 ASTMD 150
Volume Resistivity, ohm-cm   1.3 x 1015 1 x 1015 ASTMD 257
Thermal Conductivity, BTU's   20 20  



1.       Premix P.C. 282 in the original container prior to use to insure any settled filler may be reincorporated. Warming PC 282 to 100°F facilitates ease of use.

2.       Weigh out the required amount of P.C.282 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.

CAUTION: Good housekeeping rules are always important.  Provide ample ventilation in all areas of handling, mixing and use.  Avoid prolonged breathing of possible fumes.  Minimize skin contact.  Use of goggles, rubber gloves and protective creams is recommended.  Always wash exposed areas immediately using warm water and soap, followed by rinsing with clear water.  If material comes in contact with eyes, flush with clean water for 15 minutes and consult a physician immediately.

All data given in this bulletin is based on our own research and research of others.  They are believed to be accurate, however, no guarantee of accuracy is made.  Product described is sold without warranty, except conformity to specifications, and on condition that purchasers shall determine suitability for their particular purpose.