Potting heat sensitive electric parts in non heating resin

[asimpson]

I wish to pot some temperature sensitive electrical components in a hard resin that doesn't heat up above 30C during setting. Is there a slow set epoxy of polyurethane that wont heat up too much. I assume mass and area of product have effect on ultimate temperature. Part is 4" square and 3/4" high. and about 50% resin..

Thanks

 

[MintJulep]

Both epoxy and polyurethanes cure exothermically.

The temperature that they reach during curing is determined by a heat balance. The cure rate is only one of several factors.

The geometry and material of the component and enclosure and ambient environment during cure will largely determine the max temperature.

A slow-curing resin will produce heat slower.

Assuming that geometry and materials are already fixed, you can manipulate the ambient environment to limit the temperature. Control the ambient temperature, control the velocity of air.

 

[sreid]

Look at Dolphs.

http://www.dolphs.com/techtips_potting.cfm

 

[Compositepro]

Most potting resins for electronics are not very hard because this would cause a great deal of stress on the potted parts during temperature changes. They are also usually designed to be low exotherm. Fillers are often part of the formulations to lower cost and they also lower exotherm. There are plenty of potting compound suppliers, who can be found using Google.

 

[asimpson]

Thanks.