Ulta Low Viscosity Encapsulants for Electronics

[KevinZ7]

I have electronics that need to be potted with a very low durometer, water clear compound. It needs to be potted bubble free for aesthetic reasons, flow through and around some very fine features, and be a gel rather than a rubber to prevent de-lamination (separating with the wall of a clear part that becomes visible)

I have scoured the internet and countless technical data sheets.

And before anyone suggests it, Master Bond is out of my price range.

I have tried QSIL 217 (

http://www.quantumsilicones.com/2012/02/qsil-217/)

which is the lowest viscosity silicone encapsulate I could find anywhere clocking in at 330cP, however it cures dry and brittle and experiences de-lamination in use.

At the moment I am experimenting with Loctite 5623 and 5625 which has a viscosity of around ~800 cP, which is higher than I would like.

Has anyone had any experience with ulta-low viscosity silicone gels or know of any suppliers that might carry them?

 

[asimpson]

For clarity clear acrylic resin is used for displays and awards. Not wure how it would work with electronic components and heat. See attached link

http://hackaday.com/2012/04/13/free-formed-circuit-protected-by-a-brick-of-crystal-clear-resin/

 

[IRstuff]

encapsulants for LEDs come to mind:

http://www.dowcorning.com/content/e...ics_led_tutorial2.asp?DCWS=Electronics&DCWSS=

http://krayden.com/tds/dow_jcr_6122_tds.pdf

appears to have a viscosity in your range

TTFN
faq731-376

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[Compositepro]

LED encapsulants will not be low durometer. You can add silicone diluents to silicone resins, which act as plasticizers. This is how the pads for pad printers are made, and how you create a gel.

 

[KevinZ7]

Silicone diluents... very interesting! This might be just the thing I need. Googling now, but can anyone recommend any vendors (Can/USA)?

 

[KevinZ7]

So, after doing some googling, it appears that these Silicone Diluents are the same thing as Silicone Oils (they are both listed as polydimethylsiloxanes).

I already have some 0.65cst Silicone Oil at work! I will try this first thing on monday.