Xenodius - 14-2-2007 at 09:52
Hello again everyone. I have a 'noob' question.
In a given mixture, is it possible to exchange given binders like shellac, PVC, red gum, dextrin, parlon, saran, etc?
I understand in hygroscopic mixtures, dextrin is usually impossible to substitute in, but what about the others? I am just touching the iceberg on
pyrotechnics, (My parents are basically wanting me to proceed very slow into this, for safety. Which I agree, but they don't want me spending loads
of cash on it... They had not problem with guns!) and I don't want to have to buy several lb's of binders if I don't have to. I am going to be
rolling stars with several colors, hence several comps, and hence several binders, unfortunately.
Here is one of the comps I want to make:
Source: PML, post by Charley Wilson <cwilson@celsvr.stortek.com.>
Comments: Beautiful green. Direct substitution of barium nitrate with strontium nitrate produces a nice red.
Preparation: Dissolve shellac in boiling ethanol. Prime with potassium perchlorate based strobe prime
Ammonium perchlorate..............................50
Barium nitrate....................................35
Shellac...........................................15
What I want to know-- I am getting PVC and Dextrin since they are so common-- and I may have to get more, but can I exchange any binders with each
other? I heard Parlon and PVC are exchangeable.
Just trying to save money-- Besides, if I do this for a while, it will be nice to know.
Thanks for your time.
YT2095 - 14-2-2007 at 10:22
IIRC, PVC is best used for things like Copper based salts and mixtures as it`s a Chlorine donor.
DeAdFX - 14-2-2007 at 12:44
hmmm.. I am going to give a rather long explanation. I hope you can follow along.
In a given mixture, is it possible to exchange given binders like shellac, PVC, red gum, dextrin, parlon, saran, etc?
Yeah you can sub binders for each other but you must also keep in mind the purpose of the binder. Dextrin is of course used to bind stuff and that is
pretty much its sole purpose. So you can subsitute it for guar gum, xanthan gum, red gum and so on.
Depending on how you use the PVC will determine what can be substituted in and what cannot. If you are using PVC as a binder and a chlorine donor
then you only use compounds with similar abilities such as parlon and saran resin. This means you cannot use Hexachlorobenzene as it doesn't fit both
of your requirements. Now if you are using PVC solely as a chlorine donor then you can use parlon, saran and hexachlorobenzene.
Using PVC as a binder only is a waste as the chlorine won't really be used. I recommend using dextrine for most of your binding needs as your only
solvent is water which really helps with costs and toxicity. If water becomes an issue then you could use the non aqueous system of PVC + THF or PVC
+ Methylene chloride.
Now to your specific case.
I am kind of doubtful if this mixture needs anymore chlorine as there is some provided by the Ammonium Perchlorate so there should be no need for
PVC. As far as water is concerned there might an issue. If a double displacement reaction occurs between your Ammonium Perchlorate and Barium
Nitrate you will end up with two very hygroscopic compounds, Ammonium Nitrate and Barium Perchlorate. Just make a test batch of 50 or so grams and
leave the stars out in the open. If you end up with a puddle after a week then using an aqueous binding system will be an issue and you might have to
use PVC[or some other commonly available non-aqueous binding system].
[Edited on 14-2-2007 by DeAdFX]
Sweet
Xenodius - 14-2-2007 at 16:58
Hey, thanks for the input-- I will be getting both PVC and Dextrin so I will try both.
Much appreciated!