I use silicon rubber for casting KNSB (sugar) propellant grains because it
doesn't stick. I often apply Red RTV silicone gasket sealant to the aluminum
bulkheads of my motors as insulation (again using KNSB propellant) and it
sticks for that application. One of the NASA SLI teams I mentor forgot their
APCP motor seal disk used to insulate the bulkhead end of the motor. I cut out
a disk from a sheet of silicone rubber to use...it worked. Never tried applying
it directly to APCP/HTPB propellant.
From: William Claybaugh <wclaybaugh2@xxxxxxxxx>
Date: Tue, 27 Feb 2018 16:26:49 -0700
Subject: [AR] Insulation, again
Is there any reason one cannot use silicone rubber sheet for insulation?
It offers double the temperature resistance of EPDM and cost about 2/3 as
much; are there any problems bonding it to metal or bonding HTPB propellant
to it?
Bill