Firmware21 - 23-6-2015 at 08:09
Hello people,
It's been a while Im lurking this forum, but it's the first time I get something strange enough to force me to post ^^'.
I've been trying to isolate a plasticizer from pvc gloves, which should have been a Phtalate (which you know can readily be hydrolyzed to phtalic acid
and then dehydrated into the useful Phtalic anhydride).
So I first extracted the gloves (10g ) with somewhat like 200 mL of Isopropanol (Reflux for 2:30 H ), filtered of the gloves off, concentrated to 100
mL and then proceeded to hydrolyze with NaOH (20 mL, 7.5 M, reflux for 1 H).
Everything was working fine so far, until the solvent stopped boiling. There was then a wierd 2 layers mixture with a white solid in the upper one
(probably the organic layer). I decided to add HCl to the mixture (which was the next step for my synthesis) but before I even had time to do so, as I
swirled the mix, the white solid started to fizz in contact with the air and give a bad smelly gas.
Since I didn't know what was going on, I decided to keep that stuff outside, away from everything.
After a little of research, I found that phtalate plasticizers are banned in my country for safety reasons, and according to the wierd results I've
had, there wasn't phtalates in my extract.
I'm a bit worried about this gas (I wasn't wearing any gasmask, only the regular "safety apparel"), has any of you encountered this kind of problems
before ?
blogfast25 - 23-6-2015 at 08:39
Hi,
What is your country?
DEHP alternatives:
https://en.wikipedia.org/wiki/Bis(2-ethylhexyl)_phthalate#Alternative_plasticizers
Firmware21 - 23-6-2015 at 09:00
Switzerland, I've read here (http://www.bag.admin.ch/themen/chemikalien/00228/01378/?lang... , it's in french sorry) that phatalates are to be banned for toys and domestical
use PVC products (such as gloves). I assume no phtalates could have been in these gloves, but then, none of these alternatives would have given such a
strange mixture. Maybe it's something else that was contained in the plastic. In the meantime i'll probably get rid of that mixture (I need my 250 mL
RB back, and I have no use for such stuff anyway), but I'm still curious enough to try it one more time ( probably when i'll have access to better
equipement (analytic gear from university)).
unionised - 23-6-2015 at 10:47
Did you add an anti bumping agent?
Was the stuff cool or still hot when you added the HCl?
Firmware21 - 23-6-2015 at 11:53
I cooled the thing to room temperature before "attempting" to add the HCl, but the solid actually started to touch the surface of the organic phase,
and as it came in contact with air, it fizzed. So no HCl was added. No bumping agent was added. Everything happened after this hydrolysis.
Firmware21 - 24-6-2015 at 01:15
Here's a pic of what I made (and got rid of).
Orsyn - 24-6-2015 at 11:13
I'm not sure DEHP is as common as it once was, but I could be wrong.
I've done about 4-5 PVC extractions and only once got any PA. A couple times I've gotten something that looked close, but didn't behave like PA when
attempting to check the mp or make the anhydride.
Gloves, clear vinyl tubing, shower curtains.. Cheap vinyl gloves are the only thing that have worked so far, and now I can't find that brand anymore..
=/