Decomposition of VG to acrolein

[kinabaloo]

Hi Exo,

That's an interesting result. And means, among other things, that a juice with no gunk production should be possible. The nicotine, if included, will have to be a pure source and not a tobacco soak. Some flavorings will also be dry-deposit free.

Perhaps a small amount of VG can be used without decompositon - say, 10%. 50/50 if it does or not. If 10% is ok, maybe 20% can be tested; 20% would be enough to get some noticeable visible vapor improvement. Maybe even 50% could be tested as the original test used 90% VG if I remember correctly, which nobody actually uses.

Adding a little pure ethanol might help too in making a small fraction of VG usable without any decomposition,

Good work - takes our understanding forward and can lead to improvements in taste and atomizer lifespan

ps : I haven't seen SunVaporer post those yet; been 2 or 3 weeks now. Perhaps the water or PG was not pure, some old dry deposit in the mesh, something like that. Or perhaps a different protocol factor, such as % split. In fact, as I remember, the PG+water was vaped by a friend while SV vaped the VG+water.

 

[surbitonPete]

Re-read that acrolein from glycerol in tobacco smoke,
(& even though it's from Phillip Morris) it's quite enlightening.

Having second thoughts about
'glycerol just being like any burning organic liquid on a hot coil',
specifically probably similar to PG or other carriers...

cos just now observing pure PG vaping on a fresh exposed coil (550mA)
& it seem's to be producing no burnt gunk whatsoever.

We'll see what it's like after 20 to 30 ml.

Did SunVaporer post his VG vs PG results?

That seems to point to this ecopure liquid probably being 'worse' for gunking up coils because it's all VG and not PG.

 

[kinabaloo]

That seems to point to this ecopure liquid probably being 'worse' for gunking up coils because it's all VG and not PG.

Hi Pete - That is looking to be the case, yes.

I hope it is found that a small fraction of VG can be safely used.

And as some people seemingly don't react well to PG (or perhaps an impurity), we maybe need to find an alternative that is not VG or PG.

And a form of nicotine that will volatize completely.

 

[exogenesis]

This is a huge difference between pure PG & pure VG,
still no deposit at all, even with trying PG flow 'too dry' and 'too wet'.

Maybe the added water changes it completely ?,
I had to add 10% DI water to the glycerol to make it flow sensibly.

Wonder if the 'less than 20% glycerol' in e.g. TW e-liquid
doesn't give as much gunk (per amount of VG) as straight
glycerol because of the bulk PG thats there as well,
something like alcohol reducing the boiling point/ heat capacity ?

Looks like I've got a few more tests to do than I thought.


Some people have allergy or other reactions to PG,
was this the only reason the lab reports seem to
recommend using VG rather than PG?

What liquid is volatile enough, non-toxic, gives no reactions for anyone,
doesn't heat-decompose and is tasteless or has a pleasant taste ?
Is PG the closest we'll come ?

 

[kinabaloo]

What liquid is volatile enough, non-toxic, gives no reactions for anyone,
doesn't heat-decompose and is tasteless or has a pleasant taste ?
Is PG the closest we'll come ?

Water

Though a glycol is needed for the smoke effect. Just looking into dipropylene glycol and tripropylene glycol. Boiling points of 235C and 265C respectively. Both on quick glance seem similar to PG safety-wise but may share the same allergy problem for some. Raised B.P.s over PG but long-lasting, dense fog

Mineral oil (baby oil), that is mostly alkanes, is also used in some fog juices.

Very interesting results. Does lead to more hypothesis testing though But this is pioneering work (even if quite basic really!)

 

[surbitonPete]

Oh and I can't really say what the vodka did....it did make my failing mini pipe atomizer vape almost as good as new for a few days....but unfortunately it died this morning and it was my last mini pipe atomizer....I need a bit of time before I can buy any more and I am not so sure I want to risk spending more money on those.

 

[Kate]

Sedansa have started using PEG400 - polyethylene glycol instead of glycerine or propylene glycol.

 

[kinabaloo]

Pete - sorry to hear your e-pipe. Cheer you up with an interesting fact: mineral oil (baby oil) is good at removing sticky labels

Found this interesting link about safe exposure limits to theatrical fog for actors:
AEA Fog haze and Smoke Guidelines | J&M Special Effects

 

[exogenesis]

Now I'm going to have to go and get some PEG400 as well.

'Mineral oil' sounds a little undefined, is it a recognised 'formulation' ?
(edit: looks like a mixed-content by-product of the petroleum industry)


Any chance of you doing a dead atty dissection Pete ?

 

[surbitonPete]

Pete - sorry to hear your e-pipe. Cheer you up with an interesting fact: mineral oil (baby oil) is good at removing sticky labels

Found this interesting link about safe exposure limits to theatrical fog for actors:
AEA Fog haze and Smoke Guidelines | J&M Special Effects

That's so funny and kinda bizarre that you mention sticky labels .....I was in Halfords today and happened to buy a tin of stuff specially designed for removing sticky labels...(I buy every cleaning fluid I see these days!) in the hope it might have some cleaning effect on my coils.......needless to say it doesn't work.

 

[kinabaloo]

Kate - that's interesting. After a quick look into it, the only slight worry is a low flash-point.

Exo - just a petrochemical mix, available in different forms, with a range of hydrocarbons, mostly alkanes. Is used as 'baby oil' and in some fog machines, so can't be too bad (can it?)

 

[surbitonPete]

Now I'm going to have to go and get some PEG400 as well.

'Mineral oil' sounds a little undefined, is it a recognised 'formulation' ?


Any chance of you doing a dead atty dissection Pete ?

I have taken it apart exo.....and it looks just as gunky as any with the vodka juice ..so I don't really know how the vodka made it work so well. They drape some of the fibreglass wicking material onto the coil with these mini pipe atomizers and it's probably why they work so well at first ...but the fiberglass just joins up with all the gunk and becomes one big black mass on the coil.

 

[kinabaloo]

Some info on PEG 400 :

"PEG - 400 is harmless towards skin ; easily soluble in water and faintly sweet in taste. This makes it an attractive ingredient in cosmetics such as creames ; jellies and lotions . PEG-400 is added to lotions intended to have a mild relaxing effect on skin . It is easily absorbed by the skin acting as solution promoter for the therapeutic agents which can be added to the lotion. It imparts smoothness to skin but does not have a strong dehydrating effect as glycerine.

PEG - 400 is a superior and thermally stable heating medium than the conventional mediums , due to its higher molecular weight ; higher boiling point and specific heat."

Haven't discovered the boiling point/range yet.

Available in 250kg drums from: POLYETHYLENE GLYCOL

 

[exogenesis]

Thank Pete,

maybe thats a design flaw, better initial function, poor lifetime.

Certainly 901 attys I have don't have that underbridge wick stuffing,
but the 510 (Titan) one's do.

All comes together in a nice tight gunk-ball on the coil ?

edit: I'll see if I can order some EUPharm PEG400 from Boots.

 

[Letzin Hale]

That seems to point to this ecopure liquid probably being 'worse' for gunking up coils because it's all VG and not PG.

You know Pete, some of the guys on here are so obsessed with acrolein and finding that it's being invisibly produced and will kill us all if we use VG that I'm beginning to wonder if they went through all of this with cigarettes. I have yet to see one independent scientific test from them, just endless speculation. I just wish they would put the money up and have liquids tested to their demanding specifications so that we could all sleep safely in our beds.
They seem to want to ignore any contra indication of the existence of this substance, even laboratory tests and the simple test that acrolein stinks and tastes like .... when produced.
As for gunking atomisers, I have been using VG with the same atomiser for just over two months and with the aid of good daylight and a magnifying glass I can see the coil clearly with zero gunk. I'm so tempted to rip the mesh off and take a photo but it is running so well that I will resist until it gives up.
Alan.

 

[Kate]

There are a couple of forum threads about PEG, I don't know how useful they are:

http://www.e-cigarette-forum.com/fo...on/5874-peg-new-ingredient-instead-pg-vg.html

http://www.e-cigarette-forum.com/forum/health-safety-e-smoking/8404-polyethylene-glycol-400-a.html

 

[surbitonPete]

You know Pete, some of the guys on here are so obsessed with acrolein and finding that it's being invisibly produced and will kill us all if we use VG that I'm beginning to wonder if they went through all of this with cigarettes. I have yet to see one independent scientific test from them, just endless speculation. I just wish they would put the money up and have liquids tested to their demanding specifications so that we could all sleep safely in our beds.
They seem to want to ignore any contra indication of the existence of this substance, even laboratory tests and the simple test that acrolein stinks and tastes like .... when produced.
As for gunking atomisers, I have been using VG with the same atomiser for just over two months and with the aid of good daylight and a magnifying glass I can see the coil clearly with zero gunk. I'm so tempted to rip the mesh off and take a photo but it is running so well that I will resist until it gives up.
Alan.

Hi Alan ....I don't worry much over what I am vaping....in my mind it just cannot be compared to what I was smoking...the only thing that did worry me was the possibility of vaping bits of the polyester but I don't use that any more. ......I have no idea why your coil is clean though.....what make of juice do you vape?........I have tried TW and Janty and the e-cigs juicel and they all cover the coils in black gunk within just a few days.

 

[Nuck]

Given my luck with atomizers and how clean they get with a phosphoric acid bath once a month (I do no other maintenance except the odd blowout when changing flavours), and since I use pure VG almost exclusively and only drip, it is possible that the cause of a lot of the buildup that many report is the result of the cart material and the flavours.

If there is a single test that produces a positive for acrolein, I'll stop using VG that day, but it seems given the recent lab reports (1 recommended VG and the other found no traces of acrolein) that VG is currently the safest option.

 

[kinabaloo]

Letzin - I vape with VG although I suspect there is a slight acrolein expsure from it. It is not alarmist; it's just that the chemistry and evidence points to it. The denaturisation of VG also gunks up coils shortening their lifespan considerably. Then there's the bad taste, not pleasant even aside from health effects.

I am not that worried about acrolein as it is also produced by some types of cooking, as is a similar toxin called acrylamide. The tests you referred to were not set up to detect acrolein. The chemistry is that acrolein will be produced when VG is raised to its boiling point; it's just a fact.

I am working to make vaping better and better. By finding out what level of VG might not lead to decomposition, alternatives such as PEG-400, dry-residue-free flavorings (so not burnt on coil), suggesting a move to temperature-controlled heating, etc.

Even VG based vaping is most likely hundreds of times less toxic than smoking analogs.

 

[Nuck]

Letzin - I vape with VG although I suspect there is a slight acrolein expsure from it. It is not alarmist; it's just that the chemistry and evidence points to it. The denaturisation of VG also gunks up coils shortening their lifespan considerably. Then there's the bad taste, not pleasant even aside from health effects.

I am working t make vaping better and better.

What evidence points to the presence of acrolein? I also don't buy that atomizers lives are shortened (considerably) but am willing to keep an open mind. Do you have any real evidence of it?

You also seem to have narrowed down the bad taste to VG. How was this done?