Steeping Times and an Ultrasonic Cleaner Part III

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mikepetro

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Well, it WORKS!

Most of the technical gobbledygook has already been covered.

At this point I think everybody is just happy speed steeping their juice, and answering the occasional question that pops up.

Actually I do have a technical question though. I have seen various recommendations as to max temp, most were "if I recall" or "so & so said" type references. Does anyone have a a source/reference (that can be validated) that specifies exactly what temp nic starts to "lose potency"? I know nic will begin to oxidize at some temp (what temp range?), but the oxidation only affects color (not efficacy) up to some point, the question being what is the point where efficacy starts to decline.
 

Mowgli

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Well, it WORKS!

Most of the technical gobbledygook has already been covered.

At this point I think everybody is just happy speed steeping their juice, and answering the occasional question that pops up.

Actually I do have a technical question though. I have seen various recommendations as to max temp, most were "if I recall" or "so & so said" type references. Does anyone have a a source/reference (that can be validated) that specifies exactly what temp nic starts to "lose potency"? I know nic will begin to oxidize at some temp (what temp range?), but the oxidation only affects color (not efficacy) up to some point, the question being what is the point where efficacy starts to decline.

I'll ask Kurt the resident ECF chemist when I get a chance and post back when he replies.
 

dannyv45

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Actually I do have a technical question though. I have seen various recommendations as to max temp, most were "if I recall" or "so & so said" type references. Does anyone have a a source/reference (that can be validated) that specifies exactly what temp nic starts to "lose potency"? I know nic will begin to oxidize at some temp (what temp range?), but the oxidation only affects color (not efficacy) up to some point, the question being what is the point where efficacy starts to decline.

Here's a little tid bit I found.

To give a clear picture of just how unstable freebase nicotine is, let's look at a few facts about it. According to the International Programme on Chemical Safety (IPCS), freebase nicotine has the following physical properties:

Melting Point: -80 degrees Celsius
Boiling Point: 247 degrees Celsius
Flash Point: 95 degrees Celsius
Auto-Ignition Temperature: 240 degrees Celsius
Explosive Limits: 0.7 - 4 percent, by volume, in air
Vapor Pressure at Room Temperature: 0.006 kPa


The interesting thing to note here is that the auto-ignition temperature is lower than the boiling point. This means that, if you heat freebase nicotine in an air free container, it will detonate (explode) before it boils.

Nicotine is so unstable that it does not need to react chemically with anything to have an explosion occur. Its low vapor pressure tells us that nicotine does not evaporate on its own. If you heat it, nicotine will decompose chemically before it boils. Furthermore, in the presence of air, nicotine bursts into flames at a temperature just below the boiling point of water.

For a reference on the physical properties of nicotine, you can check the IPCS:
ICSC 0519 - NICOTINE

reference source:

The Smoker's Club, Inc. Encyclopedia 16

Now keep in mind that these figures are based on pure freebase Nicotine and what results in a finished mix that's steeping is diluted far below what the figures are based on when mixed in a PG/VG base. So I would say that the recommended 120F or 48.8C should be observed if heating your mix. And I would assume there would be some chemical breakdown even at the fore mentioned recommendations. How much I really don't know.

The reference article I've linked to gives some other interesting information on freebase Nicotine and is a really good read. I highly recommend reading it.
 
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Mowgli

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Here's what Kurt had to say in PM:

Kurt said:
Nicotine will react with O2 in the air at pretty much any temperature where the two molecule collide with each other.
Even cold if the liquid is, well, liquidy.
If you are talking about thermal decomposition, it should not decompose significantly at 125F, but I don't know if thermal decomp temp is known exactly.
Certainly it would need to be above the boiling point of water, so I doubt there is much thermal decomp happening at 125F.
Reaction with O2 is always increased with increasing temperature.

Mowgli said:
Hi Kurt

Someone in the ultrasonic cleaner thread asked if anyone has an actual authoritative source for a the temperature that nictine starts to degrade at.
In other words what sould the water's max temp be in the UCs.

We've been using 125° F as a generally agreed on temp but nobody remembers where that originally came from.
Do you know if that temp is close enough or where to find out?

Thanks, Mowgli
 

Scope666

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Read my post above. Slightly below the boiling point of water pure Nicotine will explode in a sealed bottle. If you heat it, nicotine will decompose chemically before it boils. 120f - 125f (48C) is a good recommendation.

I go for warm, but not hot. Comfortable enough to leave my hand in there without it being burning. As long as it's somewhat warm, it makes the VG super thin which helps it mix well with the other ingredients.
 

mikepetro

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Good read, thanks Danny.

Thank you as well Mowgli.

I know that my UC, if started with hot tap water, will easily get to 50C or above within the 99 minute timer cycle without ever turning the heat on. I may just start with cold water from now on, and dilute with cold water if doing multiple 99 min cycles.

I think Kurt's statement about "Reaction with O2 is always increased with increasing temperature" also lends itself to using the cap and filling the bottles as full as possible, while UCing, which I dont always do.

I wonder what he means by "reaction" though. Is that the discoloration from oxidation, or is that a reduction in efficacy, or both? Does oxidation equal reduced potency?
 

dannyv45

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The rest of the article is a really good read expecially where they say there is really no nicotine in the solution but a chemical compound of the by product of nicotine called cotinine, and nicotinic acid (vitamin B3, niacin). hese compounds formed from nicotine are stable, are not poisonous, are not addictive drugs, and are essential to good human health and nutrition.
 

dannyv45

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Good read, thanks Danny.

Thank you as well Mowgli.

I know that my UC, if started with hot tap water, will easily get to 50C or above within the 99 minute timer cycle without ever turning the heat on. I may just start with cold water from now on, and dilute with cold water if doing multiple 99 min cycles.

I think Kurt's statement about "Reaction with O2 is always increased with increasing temperature" also lends itself to using the cap and filling the bottles as full as possible, while UCing, which I dont always do.

I wonder what he means by "reaction" though. Is that the discoloration from oxidation, or is that a reduction in efficacy, or both? Does oxidation equal reduced potency?

The reaction he speaks of is caused by O2 and causes the NIC to brown (oxidize) but I don't believe it reduces the potency. From what I've read the temperature would need to be just under the boiling point for the chemical composition to break down.
 

dannyv45

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