[garciake]

hallo,

can somebody explain me what the numbers after the name mean?
WHat does the 20 or the 80 mean?
DOes this say something about the molecular mass of the product? or ?

thanks in advance

[sjb]

I don't think the 20 and 80 mean anything other than just an identification characteristic, looking at http://en.wikipedia.org/w/index.php?title=Polysorbate_80&oldid=215506664 and http://en.wikipedia.org/w/index.php?title=Polysorbate_20&oldid=215514576

[garciake]

I don't think the 20 and 80 mean anything other than just an identification characteristic, looking at http://en.wikipedia.org/w/index.php?title=Polysorbate_80&oldid=215506664 and http://en.wikipedia.org/w/index.php?title=Polysorbate_20&oldid=215514576

yeah, but identification based on what?

Whats the difference between tween20 and tween80? I know the structure is a bit different, but what has this to do with the 20 and 80?

I know they sometimes use numbers like in PEG , where the number behind the PEG says something about the molecular mass or chain lenght.
But what with tween?
I cant imagine that the number means nothing at all.

[macman104]

Look at this picture.  It indicates where the 20 comes from

http://en.wikipedia.org/wiki/Image:Polysorbate_20.png

But, then again, the tween 80 also adds up to 20, so I'm not exactly sure...

[garciake]

Look at this picture.  It indicates where the 20 comes from

http://en.wikipedia.org/wiki/Image:Polysorbate_20.png

But, then again, the tween 80 also adds up to 20, so I'm not exactly sure...

Well I saw this:

it means how many times you have a Ethylene oxide in your structure?
But I wonder if this can be correct?

I mean: tween 80 would mean at least 80 times Ethylene oxide , meaning at least 80 O's but thats not correct.
Its correct with the tween 20 there you have indeed 20 times a Ethylene oxide but for the other tweens it doenst add up.

[enahs]

The difference is the type of fatty acids present.

I refuse to use tween, it is polysorbate, such as polysorbate 20, 40, 60, 80.

That w+x+y+z = 20 is a coincidence.

[DrCMS]

Ask a real question and somebody might answer it.  So far you've just talked crap.

[macman104]

The difference is the type of fatty acids present.

I refuse to use tween, it is polysorbate, such as polysorbate 20, 40, 60, 80.

That w+x+y+z = 20 is a coincidence.

Fair enough.  I think the OP's question was *why* 20, 40, 60, 80.  Why not 1,2,3,4?  Honestly, I'm not sure if there is an easily findable answer.  It may not even have much of a reason, but that is what I gathered the OP was wondering.

[enahs]

The number refers to the average number of moles of ethylene oxide reacted per mole of sorbitol.

[garciake]

Ask a real question and somebody might answer it.  So far you've just talked crap.

And whats wrong with my question then?

I just want to know what the number means.
In most cases when there is a number behind the name, the number means something. (ex. PEG1000, where the 1000 refers to the molecula mass)
And I was wondering what this number specificaly means!
Is that such a strange question?




Anyway, thanks for the answer enahs!

[DrCMS]

TWEEN 20 is a polyoxyethylene sorbitol ester, with a calculated molecular weight of
1,225 daltons, assuming 20 ethylene oxide units, 1 sorbitol, and 1 lauric acid as the primary fatty acid.

http://www.sigmaaldrich.com/sigma/product%20information%20sheet/p5927pis.pdf

TWEEN 80 is a polyethylene sorbitol ester, with a calculated molecular weight of 1,310 daltons, assuming 20 ethylene oxide units, 1 sorbitol, and 1 oleic acid as the primary fatty acid.

http://www.sigmaaldrich.com/sigma/product%20information%20sheet/p4780pis.pdf

They could be called tween A and tween B.  So your question was like asking why are eggs called eggs but apples called apples?

I assume tween 20 was delevloped 1st and the 20 did relate to the 20 EO's reacted but then they developed a new related compound and simply called it tween 80.  The 80 meaning nothing but being different to 20.

What annoyed me was the pointless question you've asked here and on other forums when you could have found all the info you wanted from doing some googling yourself.

[garciake]

eum
I can understand your point of view, however I have the feeling you misunderstood my question.

There is a difference between naming a thing (just giving it a name, like why is an apple an apple) and naming a thing with a reason behind it.
And I was under the impression that the 20 and 80 ment something.
Like in organic chemitry where the numbers mean something (eg. where the structure is placed or something like that, or in peg, where the number stands for the molecular weight).
And because I couldnt find any info on why the numbers , I asked it.

And I did knew there was a difference between tween 80 and tween 20 , having other acids, but I just couldnt figure out what the link between the number and structure was.

[ericchen]

I think you may find some clue from the manufacturing process of tween 80

[gzee27]

I know I'm 12 years late but guess this might help someone.

The numbers 20 and 80 correspond to the type of fatty acid used in the esterification of the sorbitan.

Some of the examples are:

20 lauric acid
40 palmic acid
60 stearic acid
80 oleic acid

I got this from my lecturer, hope this helps!

[pgk]

I do not bring something new, but “Span” and “Tween” are proprietary names of CRODA Plc for non-ionic emulsifier, based on sorbitane esters with fatty acids. The accompanying numbers are CRODA’s code numbers that indicate the fatty acid derivative, as “gzee27” has already explained and have nothing to do with the EO polymerization number. However and due to coincidence, “Tween 20” has 20 EO in total.