Decomposition of VG to acrolein

[kinabaloo]

Interesting chart Exo; I think this % split with water. If there is something similar wrt boiling point, there might be a % of VG that does not lead to a deposit. A little bit of a long-shot but just might be the case. In this case, i would hazard that it would be when VG is a minority fraction.

Found that PEG is not broken down to EG in the body, so that's good news.

As is the no deposit with PG

[kinabaloo]

ps: It makes sense to go with the lower B.P but last night on looking into this I found the 400 version to be more well-tolerated. Seems Sedansa have done their homework

However, that was a cursory skim of information; worth looking at again as the lower BP would be most welcome.

[exogenesis]

It seems a small amount of water reduces the boiling point of
glycerol markedly.

The 30ml glycerol + 4 ml water I was using, that produced
about 1 amount gunk from 1000 amounts of glycerol should
have had a boiling point of only 133 celsius.

Don't know if you get 'partial distillation' though,
i.e. does it go back to 100% glycerol during the evaporation process?

Didn't stop it degrading though,
but possibly only that part in contact with the hot coil was making
the 0.1% denatared gunk, the majority boiling off as vapour ?

Might be worth testing other ratios to see if it make less or more
gunk with more/less water.

[kinabaloo]

Exo - good find, very interesting - far from linear and suggests a test with 50% VG (comon usage) well worth doing. Could still be fractonal distillation effects and temperature variations sufficient to still cause a deposit. But only one way to find out ...

I think we can expect less than half the quantity of deposit though, perhaps only a 1/4 or even less. Would be nice if it turned out to be close to zero

ps: ethanol might bend that curve even more I wonder ?

pps: heating a water/VG mix (50/50) on a teaspoon: separates the two very visibly; all the water evaporates first. The whole mix looks to be boiling but only in the second half, time-wise, does the characteristic fog appear. Flash heating of a tiny amount would be expected to behave very differently, but perhaps not.

ppps: judging from the 'noisiness' of the vapor test result chart, there might be an unknown number of gaseous units produced too.

[kinabaloo]

A note:

Regarding VG and atty voltage.

The boiling point of VG is considerable higher than PG (and perhaps its heat capacity also). Have been wondering on and off about the benefits or cons of running attys at a higher voltage. When a VG based juice is used there just might be an advantage in a higher voltage. The reasoning being as follows. If the temperature reached is lower than for ideal flash heating, a portion of the VG might remain after an activation (puff) as the juice partially undergoes fractional distillation. This increases the concentration of VG (%wise) of the juice on the coil for the next puff, raising the BP for the mix; in other words it is self-reinforcing. The temp is just enough to favor decomposition moreso than evaporation and the effect is increased deposits; whereas a higher voltage, higher temperature, setup would maximise vaporisation (but some decomp of VG would still occur).

Separate issue but worth noting:

Higher voltages are also more likly to burn the dry residue of the juice (principally the flavoring). This could cause noticeable bad taste/smell, but also potentially completely burn off some of the deposit reducing the deposit quantity.

[kinabaloo]

Well, as I've only lurked while Pete, Exo and Kin have been doing their research (I think I piped in only once or twice to thank them for what they have been doing), I want to again thank them. They are not suppliers, they are not being paid for the research they are doing on behalf of all of us.

Just want to thank you guys again and hope you continue to post your unbiased results. Cheers!

Apologies for the delayed response Jacksid. Much appreciated

I am commited to vaping and only seek to improve both the vaping experience and our understanding of it. If we can conquer the deposit issue (and intolerance issues), and I believe we can, then this will be a big step forward. It feels great to play a small part in something that could touch on so many lives - if vaping can more widely replace smoking as it reasonably should. We might have to say farewell to VG, but there are alternatives. Dry residues from flavorings are the big factor remaining; and it could be worked out in just days once the issue is addressed.

The dry residues were known about before i even got into this, but so far little thought or action seems to have gone into addressing it. The 'well, attys are fairly cheap, no big deal to replace them every so often' is reasonable to a point - but involves accepting slowly diminshing performance, bad tastes and unknown toxins (tiny though they may be, but inhaled everyday). As we can eliminate the problem we should aim to do so. Attys will still not last forever, but could well last a lot longer.

[JaneDoe]

Can anyone put this glycerin fear in perspective? What do you think is the bottom line here? Fear of acrolein/VG is the reason I am waffling and keep going back to analogs and I can't vape PG.

Any ideas about comparing the analog risks to the VG risks? I know it's a great unknown, but what are your thoughts? Is acrolein DEFINITELY present in VG vapor or possibly? If it is definitely in there is it a sure health risk or a potential risk?

Cigarette smoke definately does contain acrolein. So does air pollution.

[kinabaloo]

Cigarette smoke definately does contain acrolein. So does air pollution.

That's true. And most cigarettes contain glycerine as a humectant (probably explanatory, possibly coincidence)

It's not yet confirmed that any acrolein gets into the vapor; but there probably is a bit, but likely not too serious - long term maybe, but no cause for alarm, just needs more investigation.

PG is good to go. PEG-400 is looking good too and might be a suitable alternative to VG for those with PG sensitivity.

ps: it feels very awkward to make any statement about such matters. I can only offer a best guess. There might well be an issue but it's not something that deserves panic. Could be worse than I think (unlikely as acrolein has a noticeably terrible smell) or no real problem at all.

But what we do know now for sure is that VG produces far more deposit in the atomizer (not a good sign - as well as not good for the atomizer).

pps: if the point is that analogs are surely worse, it's easy to agree with that. So if you've switched from analogs, there's every reason to not be too worried. Give it a bit more time for the 'bottom line'; we can make vaping even better.

Hmm, now I think i'm perhaps being too glib. In simplest terms, 'i don't know'. Acrolein does appear in the Ruyan results (very small amount) and the tests where it is 'not detected' - well, don't read too much into that as even the nicotine had to be inferred. There probably is a tiny bit (the science suggests that) but there is a tiny bit in the air too, even in some foods.

For what it's worth, I am still vaping with VG. But I will also continue investigating this.

If PEG-400, for example, checks out well when Exogenesis tests that (and low dose VG still shows a problem), then it seems sensible to move from VG to that. Unfortunately it is not, as yet, so easy to get hold of for cutting at home.

[toughdiamond]

Hmmm.....does anybody know how to find out whether a particular nicotine liquid contains VG or PG? I'm using one that has very little in the way of manufacturer's info - it's quite nice but I'd like to know which type it is.

It's called e-liquid (by e-home: high-nicotine, Marlborough flavour), from Amazon. I can't post the link because I haven't made enough posts yet - I was just wondering if anybody knew, or whether there's a simple practical way of determining this just by observation.

[Sun Vaporer]

Hmmm.....does anybody know how to find out whether a particular nicotine liquid contains VG or PG? I'm using one that has very little in the way of manufacturer's info - it's quite nice but I'd like to know which type it is.

It's called e-liquid (by e-home: high-nicotine, Marlborough flavour), from Amazon. I can't post the link because I haven't made enough posts yet - I was just wondering if anybody knew, or whether there's a simple practical way of determining this just by observation.

Tough--Unless it is made by Johnson Creek, it is more then likey PG--only JC has the NON-PG option that I am aware of--most of all the rest are PG----Sun