The Vespiary

The Hive => Chemicals & Equipment => Topic started by: 96480 on March 13, 2003, 12:00:00 AM

Title: GBL as a solvent
Post by: 96480 on March 13, 2003, 12:00:00 AM

In this story I am writing I wish to be as real to life as possible-My question, if someone had GBL stored in a beaker and wished to stopper the beaker using a cork, would the gbl if it was in contact with the cork dissolve, deteriorate or damage the cork so as to break the seal??

Title: Why a beaker ?
Post by: littlejasebee on March 13, 2003, 12:08:00 AM

What SWIM would do is not to store it in a beaker but to store it in a PET plastics bottle with a lid .Why do you want to store it in a beaker with a cork   ? .

Littlejase      :)      .

Title: You should rather use a proper bottle with a...
Post by: Rhodium on March 13, 2003, 12:12:00 AM

You should rather use a proper bottle with a chemical-resistant cap. PET is a polyester plastic which is slowly dissolved by GBL.

Title: Mistated question
Post by: 96480 on March 13, 2003, 12:25:00 AM

I am trying to determine if gbl affects simple materials such as cork for a hypothtical reason, thus really being able to use the correct materials for storage are not the issue. As we are all cunducting hypothetical exiperiments here anyways ;) --you guys have been very polite which I apperciate being so unknowlegable about such advanced items as you guys tackel in your forums.
   The real question being would my theory about using the cork be acceptable for a short period such as 7 days?

Title: Well thats what SWIM sould
Post by: littlejasebee on March 13, 2003, 12:27:00 AM

Sorry Rhodium your right thats what SWIM sould do and if you don't have a proper bottle with a  chemical-resistant cap then Swim would put it in a PET plastics bottle . But not a breaker with a cork  .

Littlejase      :)      .

Title: polyester?
Post by: urushibara on March 18, 2003, 09:52:00 AM

pardon my ignorance, but is polyethylene a polyester? that doesn't sound right to me. _P_oly_ET_hylene note the upper case bits. polyethylene is okay with alcohols but is slightly damaged by chlorinated solvents and aliphatics, and a lot damaged by ketones and aromatics. afaik.

worth looking at the info about materials/solvents compatibility that is either linked from here or rhodium. some materials just turn to goop with some solvents. like acetone and nylon... man.

Title: Polyethylene isn't an polyester,it's structure
Post by: raffike on March 18, 2003, 12:06:00 PM

Polyethylene isn't an polyester,it's structure goes like
-CH2-CH2-CH2-

Title: 'ene' implies a double bond
Post by: urushibara on March 18, 2003, 08:07:00 PM

'ene' implies a double bond

what you drew would be called a linear alkane.

ethylene looks like this:

    H
    |
H-C=C-H
  |
  H

thus polyethylene would look like this:

    H   H   H   H 
    |   |   |   | 
H-C=C-C=C-C=C-C=C-H
  |   |   |   |  
  H   H   H   H  

though probably longer usually.

that doesn't come out with a monospaced font for me, is that how it is for everyone else?

how about this:

CH₂=CH₁-CH₁=CH₁-CH₁=CH₁-CH₁=CH₂

polyester would have to have oxygens and OH's in it just like an ester does.

edit: pardon me, I put too many hydrogens in previously, I've corrected this now. thanks badbody

Title: OK but how about Cork??
Post by: 96480 on March 19, 2003, 04:01:00 AM

Ok so its ok on plastics but how about cork???

Title: Normally you'd be right, urushibara.
Post by: Ziqquratu on March 19, 2003, 07:02:00 AM

Normally you'd be right, urushibara.  "ene" does normally imply double bond.  In this case, however, ethylene is the monomer.  The pi-bond in one ethylene molecule breaks and connects to the next one, forming a sigma-bond between them, which causes the pi-bond in the second to break, which joins to... and so on.  The equation would be written:

x(H₂C=CH₂) --> ...-CH₂-CH₂-CH₂-CH₂-...

The name of a polymer like this tends to be written Poly-<insert name of monomer here>.  For example, Poly Vinyl Chloride:

x(H₂C=CHCl) --> ...-CH₂-CHCl-CH₂-CHCl-...

Or even Poly Tetrafluoroethylene (Teflon):
x(CF₂-CF₂) --> ...-CF₂-CF₂-CF₂-CF₂-...

Does that make it clear?  I'd post a reaction mechanism (complete with curved arrows!) to make it clearer, but you can find them in an average text book, plus I have no idea of how to post pictures!

Title: polyethylene=long chain linear aliphatic?
Post by: urushibara on March 19, 2003, 08:18:00 AM

so polyethylene is a similar chemical in structure to hexane or dodecane or something then?

Is the plastic in naptha bottles polypropylene or polycarbonate? or does that vary?

Title: Yeah,i wondered too...but look what this ...
Post by: raffike on March 19, 2003, 12:53:00 PM

Yeah,i wondered too...but look what this document has to say about polyethylene

http://www.nrc.ca/irc/cbd/cbd154f.html (http://www.nrc.ca/irc/cbd/cbd154f.html)

(https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000416280-file_5lrs.gif)
No double bonds...which made me wonder why it is called polyethylene...
Raf is no chemist by any means,i'll see what a chemist i know(swiraf's dad) has to say about that.

Title: eh...
Post by: hypo on March 19, 2003, 12:57:00 PM

> No double bonds...which made me wonder why it is called polyethylene...

because it's polymerised ethylene (duh!)

i'd guess that there's side links to a varied
degree, giving PEs with different properties...

Title: Why not polymethane?
Post by: raffike on March 19, 2003, 01:34:00 PM

Why not polymethane?

Title: Because it is made from ethene, not methane.
Post by: Rhodium on March 20, 2003, 12:31:00 AM

Because it is made from ethene, not methane.

Title: Glad to help
Post by: 96480 on March 20, 2003, 10:19:00 AM

;D Seriously, I am glad to see you guys battle it out over plastic, it actually has brought things into perspective, I am sorry to post on a group sooooooo far over my head--yes Im intelligent just not in chemistry, but as a favor to swim, if anyone wants to play and tell me what a solvent such as GBL would do to a inert organic material such as cork well, then maybee ill put up more posts for you guys to battle over ;) ---thanks, keep laughing, posting and smiling.

Title: So ...I'm Stupid...
Post by: callen on March 22, 2003, 05:49:00 AM

Title: You just drink it
Post by: gabd on March 22, 2003, 05:15:00 PM

for a hell of a good time!
Its used as a solvent for cleaning electronic circuits, but most people I think people like to drink it more then they like like do clean stuff with it!

Title: plastics...
Post by: hypo on March 22, 2003, 05:26:00 PM

> _P_oly_ET_hylene note the upper case bits.

not really.

PE = polyethylene
PET = Polyethylenterephthalat

(but apparently PET is used for all kind of polyesters)

Title: swim knows what to do with it
Post by: 96480 on March 26, 2003, 02:47:00 AM

swim wants to know what it will do to cork--not pet or polyester or hdpe, Im just curious about cork---anyone see a trend in my question ::) Please how does gbl affect cork ::) Im begging at this point.Or is it that none of you know ;) --ha, a challenge--I dare you to answer ;D

Title: Cork contains
Post by: hCiLdOdUeDn on March 26, 2003, 02:51:00 AM

Suberin (45%) - the main component of the cell walls; responsible for the resilience of the cork

Lignin (27%) - the binding compound

Polysaccharides (12%) - components of the cell walls which help define the texture of the cork

Tannins (6%) - polyphenolic compounds responsible for colour

Ceroids (5%) - hydrophobic compounds that ensure the imperviousness of cork

Mineral water, glycerine, and others make up the remaining 4%.

GBL can cause some deterioration and wear to the cork. Use glass vials with ground glass stoppers for maximum storage longevity.  ;)

Title: many compliments and great respect
Post by: 96480 on March 30, 2003, 06:41:00 AM

A true master of life---I truly thank you for your time and the amazing wisdom you have helped bring to us all---these are real praises--thank you soooo much for responding to the heart of the thread--  thank you thank you thank you--  I knew you couldnt resist a challenge ;D  
may the sun be upon your face
the wind at your back
and your glass always half full