Hi All,
It became more and more clear for me that I have inherent fancy for making
exotic propellants. One of ideas that never leave me in peace is to make
homogeneous solid propellant with oxidizer and fuel completely solvable in
each other. I tried to dissolve AP in various potential fuels, such as
sucrose, sorbitol, polyethyleneglicol, triazole, benzotriazole,
dimethylsulfoxide, etc. at ambient temperature and up to 120°C. (to my
surprise, AP is stable at that temperature) Neither of these mixtures was
homogeneous or at least pourable.
BUT LiClO4 !
The first attempt was successful. I mix 70% LiClO4 / 30%
epoxy+curative(maleic anhydride - for high temperature processing), heat to
150°C and mixture became clear liquid (well, brown liquid), all bubbles
readily released. After heating 2 hours at 150°C mixture was still liquid
and after cooling I had hard plastic-like mass.
Summary of some test results:
Thermal stability
I put small piece (~0.1g) on the top of hot plate (black iron surface) and
turn on power. At 130°C propellant melted, at 180°C began to bubble, at
230°C became dark-brown solid porous mass. I heat it up to 290°C, but it
don't ignited. I concluded that preparation of propellant at 150°C is
reasonably safe.
Burn test
I poured hot propellant in paper tube (ID=9mm) and lit it after cooling. It
burned vigorously, ambient pressure regression was 2 mm/s. It is comparable
to what I have with uncatalised AP/epoxy 80/20 (2.7 mm/s). Flame color was
not as red as I expected.
Performance prediction
PROPEP gives maximum Isp=233 for LiClO4/ SHELL EPON 815 78%/22%. (D=
0.06993 LB/CU-IN OR 1.9358 GM/CC).
70/30 mix has Isp=221. (D= 0.06534 LB/CU-IN OR 1.8087 GM/CC)
For AP/ SHELL EPON 815 maximum Isp=249 (87%/13%). (D= 0.06422 LB/CU-IN OR
1.7777 GM/CC).
80/20 mixture has Isp=238. (D= 0.06152 LB/CU-IN OR 1.7030 GM/CC).
Does anyone have thoughts about possible pressure exponent for this
propellant?
Thereby, LiClO4/epoxy propellant has advantages:
- very simple preparation. Finished grain may be prepared during 3 hours.
- high performance (possible).
- high density.
It is expensive, however.
Serge Pipko
Anthony Colette wrote:
>
> Be very careful with homogenous mixtures of fuels and oxidizers. They
> can detonate high order. And just because it was apparently stable at
> 290' C doesn't mean it will be indefinitely. Neither will it
> necessarily be indefinitely stable at 150' C either. Such mixtures
> can be very impact sensitive and have high burn rate exponents. Be
> careful.
See also Patent No. GB 1047474
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