Sourcing Propylene Glycol locally

[BHuij]

I ordered some propylene glycol online to mix up Phenindone. Unfortunately the shipping got delayed and I’m not a patient person. Everything else I need to try out instant mytol is already here.

Do hardware stores carry this stuff or is there somewhere else I could reliably find some today?

 

[Donald Qualls]

You can make a phenidone stock solution in 91% isopropyl alcohol available at most pharmacies. Propylene glycol is superior (the phenidone will keep a little longer in that), but this works; I've used it.

Be sure you get 91% or higher; lower concentrations have too much water to preserve the phenidone.

 

[AZD]

The stuff you’ll find at the hardware store, RV antifreeze, probably won’t work as it is something like a 40/60 mix of glycol/water, plus a small percentage of dye and whatnot. We used this a lot at work for a few years, I’ve never seen a more concentrated version, though it might exist.

 

[relistan]

Places that are for mixing your own vape stuff apparently have it, or places for aromatherapy. I have just gotten mine on Amazon. But you might try that.

 

[BHuij]

Good info all, thanks. I don't vape but I think there's a vape shop close by my house. I'll check it out today. If that doesn't work I do have I think 95% isopropyl on hand. To get me through the next week or so until the glycol gets here, that should work fine.

Is there going to be any meaningful difference in a batch of instant Mytol where I use 1.5ml of phenidone solution mixed up in alcohol, vs a batch where I used 1.5ml of phenidone mixed up in glycol?

 

[relistan]

Good info all, thanks. I don't vape but I think there's a vape shop close by my house. I'll check it out today. If that doesn't work I do have I think 95% isopropyl on hand. To get me through the next week or so until the glycol gets here, that should work fine.

Is there going to be any meaningful difference in a batch of instant Mytol where I use 1.5ml of phenidone solution mixed up in alcohol, vs a batch where I used 1.5ml of phenidone mixed up in glycol?

No will be absolutely no difference. Go for it

 

[BrianShaw]

You can make a phenidone stock solution in 91% isopropyl alcohol available at most pharmacies. Propylene glycol is superior (the phenidone will keep a little longer in that), but this works; I've used it.

Be sure you get 91% or higher; lower concentrations have too much water to preserve the phenidone.

This reminds me of morning coffee break with Tom Hoskinson. He could talk for hours on this topic… once he got started. LOL

 

[albada]

Here are a couple of techniques for measuring tiny quantities.

1. Weigh out 8x or 16x what you need. Do the following 3 or 4 times: Gather the powder into a pile, and divide the pile in half. One half goes back into the bottle. After 3 or 4 successive gather-and-splits, you'll have the quantity you want.

2. Weigh out 10x what you want on to a smooth surface. Arrange the powder in a straight line of uniform thickness. With a ruler, measure the length of the line, and take 1/10th of that length off one end of the line, giving you 1/10th of what you weighed out.

I'll guess that these techniques will give you what you want within 20%, which is probably close enough.

Mark

 

[BHuij]

No will be absolutely no difference. Go for it

Turns out the IPA I had on hand was actually 99%. So I mixed up the Phenidone solution; how long should I expect that to last in a sealed glass container?

In any case, just ran my first roll of FP4+ through the instant Mytol at stock strength, and results look good. I’ll know more when I have a chance to measure densities and try printing the negs, but I’m encouraged so far.

 

[relistan]

Turns out the IPA I had on hand was actually 99%. So I mixed up the Phenidone solution; how long should I expect that to last in a sealed glass container?

Months, a year or more probably.

In any case, just ran my first roll of FP4+ through the instant Mytol at stock strength, and results look good. I’ll know more when I have a chance to measure densities and try printing the negs, but I’m encouraged so far.

Awesome!

 

[John Wiegerink]

I just walk over to my Family Farm and Home store and buy my Propylene Glycol in a gallon jug.

 

[koraks]

Turns out the IPA I had on hand was actually 99%.

It'll hydrate back into 95%-96% over time though. https://en.wikipedia.org/wiki/Azeotrope
Not that it matters all that much.

I once made a 1% phenidone stock using plain 96% bioethanol. It yellowed significantly faster than a similar stock in polypropylene glycol. I pick up my glycol from whomever happens to sell it, but it's always online. Around here, larger quantities are cheap to get from farmer's supply stores as it's apparently used to stimulate milk production in dairy cattle. Since those quantities far exceed what I realistically need, I just google around until I find a place that sells something like a liter for a decent price. That generally lasts me a pretty darn long time.

 

[Donald Qualls]

Turns out the IPA I had on hand was actually 99%. So I mixed up the Phenidone solution; how long should I expect that to last in a sealed glass container?

The solution I made in 91% lasted more than six months stored in my office, but wasn't still good after ten years, seven of those in a shed.

 

[ags2mikon]

Here is where I get mine. https://www.tractorsupply.com/tsc/p...ealth-usp-propylene-glycol-1-gal?cm_vc=-10005

 

[mrosenlof]

I've also used denatured alcohol (u.s. name, methylated spirits some other places?) for a phenidone stock solution.

 

[Donald Qualls]

Any solvent that will dissolve phenidone and contains little to no water (but is miscible with water and photographically inert) can do this job. High percentage isopropyl or (denatured or methylated) ethanol are good choices, as is propylene glycol. Polyethylene glycol (used in non-toxic antifreeze) likely would work also.