Quote: Originally posted by Lotilko  | I was reading about furazans and furoxans and I found this document. It's sadly in chinese, but it gives the densities and detonation velocities of
some highly energetic nitramines. I am primarily interested in HHTTD and compound 3, which appears to have a extremely high VOD and density. Could it
outperform ONC, or is this about theroretical preparation of these materials? I know the flourine atoms cause the high density, but also there is no
oxygen in the molecule. Maybe the lack of oxgen inhibits the formation of COF2, which would be a loss of fluorine so instead, HF forms
which has a relatively low mass. What are your thoughts on this? Sorry if there are any mistakes or errors, this is my first post and english is not
my first language. Any help will be appreciated, thanks.
|
Looks like some of the chemical pathways are purely theorical...or practically impossible (like joining a second cyclo penta-ring from a dibromo
compound itself generated by addition of Br2 onto a cyclopentene what is known to happen in trans addition (thus both Br atoms are not on the same
side of the pentaring plane...)).
Some pathways with the yields aside are plausible and probably inspired from related internationnal litterature.
Like many writing, the densities and VOD are exagerated or based mainly on thermodynamic calculations (much cheaper than actual testing and
measurements whitout the need to synthetise much material (testing may require a kilogram))...this effect is sadly true for all big HEM lab...like
Klapote's...
Now most follow the rule: "Publish or perish"...so quality of the work is less because they focus on the quantity.
SIDE NOTE:
Lately I have noticed that Klapote's team had made a mistake in most of their publications....they based their detonic calculations onto the density
of the molecule at the X-ray diffraction temperature (-100°C) what is not the normal use T°.
In fact by using the density at -100°C you overestimate the density vs at 20°C and all related detonics parameters are thus much higher and looks
sensational/promising...
Now since past year they have applied an automatic correction based on dillatation coefficient in a way to extrapolate the density of the crystals
from -100°C to the standard temperature... this might look a good idea to reduce the biased density value since contraction or dillatation may be
considered linear into a 100°C range (or more for certain compounds).
But it is not a good idea because:
1°) They use a single dillatation coefficient...while each compound and each specific crystaline form has a specific coefficient (sometimes dependant
on the axis ... thus anisotropic)
2°) Most compounds tends to srink and increase their density while cooling but it is not always the case!
3°) Some compounds change crystalline form by passing from -100°C to 20°C and this will affect the dillatation coefficient that may change
dramatically or even change sign (thus instead of srinkage you get dillatation)
So their calculation are purely indicative and quite uncertain.
About your fluorinated compound n°3, you said that there is no oxygen but you missed the point that it is only the amine skeletton on what you
perform the nitration to get a nitramine...and nitramine by definition is -N(-NO2)- and so it does contain 2 oxygen atoms!
Also perfluoromethyl (CF3-) would be as bad as teflon thus unreactive and inert...(except maybe with very reactive/reductive metals (Na, K, Li, Mg,
Al) with what it does make kind of thermites if well divised and homogeneously/intimately mixed)
You obviously confused difluoroamine energetic group (-NF2) which like related dihaloamino group (-NCl2, =N-Cl, -NBr2, =N-Br) in hydrocarbon skeletton
are energetic owing to the easy release of halogen and combination with the hydrogen as HF, HCl or HBr générâtes the driving force of the energetic
decomposition...the remaining C usually stays behind...
[Edited on 11-7-2016 by PHILOU Zrealone] |
