isopropanol

[leedrill]

might be a silly question but is there any reaction {with any of the main pyro chems } to stop me from using ethanol instead of isoprop when ricing i know mainly when acetone is needed but for prime coating stars and similar applications is ethanol any different

[Arthur]

My allergic reaction is to the cost! I hate buying solvents when water will do! Review you needs and see whether water will be the economic answer.

[schroedinger]

Nope, there shoud nothing happen.

 

It's probably better if your using Isoprop. If it gets oxidised, it*s becomming Aceton, Ethanol is becomming garlic Acid, or Ethanal.

[leedrill]

so id take it that acetone would be better than isoprop due to this explination id say that the isoprop is breaking bonds somewhere to steal the oxygen to make acetone i will rule out ethanol as viable if it is make acids of any form but would this be right to assume acetone would always be better off than isoprop

[leedrill]

can anyone out there with any advanced chemistry knowledge confirm my assumptions

[leedrill]

and as to schroedingers comment id be happy to use water for all applications but to be honest i am not sure if there is any affect from the solvents other than drying quicker from what i have read nothing states i wont get desired effects without {other than some star comps} which seem to state solvents are needed but i assume this is only when making parlon based comps but if water is only needed to activate dextrin or something id be happy to just use water but i can produce almost 98% ethanol at home and was hoping to make all drying of comps quicker even if just a 50/50 water to solvent mix could be applied i see this as less time in the open which is a pet peeve of mine having comps lying out in the sun please help me with a concise answer somebody

[schroedinger]

Just by chemical means, aceton will be best, as it's quite hard to be oxidisded.

 

But to most oxidisers won't be strong enough to oxidise them. So no worry`s about that.

 

If you get 98% Ethanol for free just use it, but be aware that you will need different binders.

 

The thing about 1:1 Watter Alc should be, that most things won't dissolve in it, so you not getting any large crystalls in your mix.

 

But allways be aware, if your using Watter and metal, (specially Al and Mg) they will form Hydroxide. This is exothermic (but quite slow reaction), so allways add some weak Acid if using Watter/Metal (for most one the normal Boric Acid will work out fine)

[leedrill]

thanks schroedinger that seems to answer my question quite nicley

[Mumbles]

I see all sorts of bad information in this thread. It wont matter what alcohol you use for the most part. You're not going to be oxidizing anything in the conditions involved in binding stars.

 

Pair your solvent with your binder. If you're planning to use parlon, then acetone or toluene/xylene will be required. Alcohol will not work. If you're planning to use red gum, shellac, or phenolic resin, then alcohol is required. Acetone may also work in this instance, but I avoid it if I can. If you're planning to use dextrin or SGRS, then you'll need water. Adding alcohol to the wetting water will diminish the binding power of dextrin or SGRS if you get the concentration too high. 50% alcohol is almost certainly too much. SGRS is apparently much more sensitive to this effect than dextrin. I really only add enough alcohol to break the surface tension. Using more just increases the costs without much decrease in drying time in my opinion.

 

Just to clarify something, boric acid is used to prevent a reaction between potassium nitrate and aluminum specifically. Never use boric acid with magnesium or magnalium. It will actually cause an adverse reaction, instead of preventing one. I find that boric acid is really only required when dealing with compositions containing flake aluminum and basic chemicals like sodium oxalate or sodium bicarbonate. The adverse reaction that boric acid prevents is base catalyzed.

 

If waiting for stars to dry is a "pet peeve", you might want to find a new hobby. This one doesn't do well with impatience. A drying box might be something to look into if you're more not a fan of having exposed composition. Even with water, most stars will be dry overnight at most.

[leedrill]

thanks mumbles that is what i meant by a concise answer. and find a new hobby don't be silly haha just where im living i dont have a shed so dont like comps lying around the house i keep most things pyro when mixed in my container which is far enough away from the house but is completely sealed i need to put 2 x whirley birds on top and turn it into a drying box itself i have a big dehumidifier i will just run a lead to the container so just will have to invest in a few hundred meters of extension chord but thank you so much for your answer i think now i see this topic the way i should and to be honest no impatience is ever involved with me making anything just in australia is best to not have comps or stars just laying around on the verandah i feel this way any way i enjoy my life and would like to keep living it but i think mumbles just ended this topic thanks

[marks265]

I am with Arthur 100 percent. I use very little of "other" solvents. Distilled water and a starch binder is what I use as much as possible. I surely never used alcohol because the word red gum was present. I only use alcohol in a proper manner. Also boric acid does not always help in dealing with oxalates even in stronger concentrations. I also believe that if you need to use alcohol to break the surface tension you may also be in the wrong hobby. This thread has run amok and should have been in the newbee section.