Replacing Parlon with Saran

[Wiley]

Is it okay to replace parlon with saran resin in Independence Red, or in Ned's variation of the formula?

 

Brilliant Red Star Formula for Screen Sliced Stars

Strontium nitrate 53%

Magnalium 19%

Parlon17%

Red gum11%

 

Saran is soluble in acetone, and it's supposed to liberate more chlorine than parlon does.

Edited May 10, 2012 by Wiley

[Potassiumchlorate]

If anything it should be better than parlon, though chlorine isn't that crucial for strontium as it is for barium and copper.

[dagabu]

Is it okay to replace parlon with saran resin in Independence Red, or in Ned's variation of the formula?

 

Brilliant Red Star Formula for Screen Sliced Stars

Strontium nitrate 53%

Magnalium 19%

Parlon17%

Red gum11%

 

Saran is soluble in acetone, and it's supposed to liberate more chlorine than parlon does.

 

Yes but you have use more, sorry I don't have those numbers here...

 

-dag

[Potassiumchlorate]

The red gum isn't really necessary in a magnesium/magnalium fueled star, by the way. You can simply raise the metal fuel to 30%; Bleser Red Mg has 28% Mg and no red gum.

[FlaMtnBkr]

Saran has more chlorine so I would think you would need less than the called for parlon.

 

I also didn't think Saran was easily soluble, including using acetone for the solvent. This is something I have read so don't know for sure. If true then using the chlorine donor and acetone as the binder won't work. Adding another binder would seem like it would work unless using hygroscopic chemicals like the strontium nitrate and counting on the parlon, or substitute, to waterproof the stars.

[Wiley]

The red gum isn't really necessary in a magnesium/magnalium fueled star, by the way. You can simply raise the metal fuel to 30%; Bleser Red Mg has 28% Mg and no red gum.

 

 

Yes, but red gum costs $10 a pound and Mg/Al costs $15 or more a pound . Pyroguide (not always reliable) states that acetone dissolves saran. However, almost any pyro supply place that gives a short description of their chemicals (such as American Pyro Supply or Skylighter) will state that saran's solvents are xylene or acetone.

Edited May 10, 2012 by Wiley

[Potassiumchlorate]

Yes, of course metal fuels are more expensive than red gum.

 

Speaking of red gum: with 11% red gum, you can use the red gum as a binder and alcohol as a solvent. Since you use MgAl and not pure Mg you don't have to use the parlon or saran as the binder. You could even add 5% dextrin and bind with water/alcohol 75/25.

[Mumbles]

I saw someone state on passfire the other day that Saran does not have the same binding properties that Parlon does. I've never tried to wet saran with acetone. It may be a situation similar to PVC where acetone just makes it swell and soften, and is not a true solvent. To really take advantage of the full binding properties you'd need to really fully be able to dissolve it. On the plus side, you'd hopefully get rid of that ugly incandescent tail that parlon bound stars leave.

 

Saran is a better fuel than parlon. Given the higher chlorine content and this fact, you could probably knock the saran down a few parts and add more strontium nitrate. Probably not too critical though.

[Potassiumchlorate]

You don't see those tails very much, if the stars burn very quickly. My red and magenta parlon stars have almost no visible tails when used in a shell.

 

I think he should bind with red gum or with +5% dextrin.

Edited May 11, 2012 by Potassiumchlorate

[Wiley]

Is it possible to add +5% dextrin to the above formula (parlon replaced with saran), add water/alcohol until the mix is a stiff dough, and produce cut stars? What kind of drying time shoud I expect, assuming that the stars are placed on a screen in a warm, dry place with a fan blowing on them?

[FlaMtnBkr]

Sure it can be done, we just don't know what the result will be. You should be able to get them dry as long as they don't get driven in so the center never dries. I would think drying them slowly would be the key but others may have a better suggestion.

 

The burning speed may be altered with the use of saran and addition of dextrin. The only way to know is make some and put them in a shell and see if you like the way they look.

 

Make 200 grams worth of stars and put them in a 3" ball shell and see if you like them. If you don't make shells that big then make only a 100 gram batch. With a layer of prime that should make enough stars to test.

 

You may also have issues with the strontium nitrate absorbing water into the stars. But maybe not? I would store the stars in multiple bags and inside an airtight container. I personally would throw in a bag of dessicant but that may be going overboard though it does get fairly humid here in Florida.

 

Let us know how things turn out.

[Potassiumchlorate]

Depending on the relative air humidity where you live, it might be a problem with the strontium nitrate, yes. I forgot that. Red gum might be the best after all.

[Mumbles]

These stars were based off of some of the Independence Fireworks formulas initially I believe. Below is probably the original, and is the closest to the above formula. It already has dextrin in it.

 

Strontium Nitrate - 50

Magnalium (-200 mesh) - 18

Parlon - 16

Red Gum - 10

Dextrin - 5

Total - 99 parts

 

There are several other variations, some using primarily saran resin. A lot of their formulas use a blend of parlon and saran. They're on passfire if you're interested. The typically have a a little higher oxidizer content and little lower red gum content. If you wanted to modify the formula I just posted I'd start around 55 strontium nitrate and 6 red gum with all else being the same.