There was a great report put out by I think Ames , or Langley , (it was
listed in NASA tech briefs) that discussed the pyrolysis of Polyimides ,
I might have a copy , I'll check
Russ
 ----------
From: Alderete, Michael
To: [log in to unmask]
Subject: [TN] FW: re Polyimide, temperature for discoloration and /or
pyrolosis [charring]
Date: Wednesday, May 19, 1999 2:30PM

rejected [why??}, and resending message below

 -----Original Message-----
From: Alderete, Michael
Sent: Wednesday, May 19, 1999 11:24 AM
To: 'IPCtechnet'
Subject: Polyimide, temperature for discoloration and /or pyrolosis
[charring]


Help.

Anyone know what temperature polyimide [in PWB]:
a. starts to discolor
b. pyrolizes, or chars?

Had similar problem at the last company- 3 phase power, 115V AC, runs
into
rig-flex backplanes on F/A-18 targeting pod. Water [salt water or wash
down
fluids] was getting into vented elec boxes, and shorting out the 3 phase
power. Fire and black stuff all over inside of box resulted.

Know very little about current design and circumstances, but our guys
think
it's a short induced problem. PI material darkens; don't think they see
charring in this instance.

Thanks in advance

Michael

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