EUDRAGIT®
High performance products for innovative technologies and processes
*Note*
This is a technical data thread...add to it at will, as it pertains to further discussion and enlightment from a solutions standpoint.
Please avoid the urges to seek solutions in this thread to the individual problem you may be faced with.
Start a new thread for answers.Concerning this subject, Geez stated..."We need to pool our observations to find a weakness to exploit. If we do not hang together, we are all going to be sleeping a lot longer than we want."
With that said....let's embark on this exploration collectively and cooperatively.
I know it's hard, but Please refrain from replying to this thread with details of your individual problem seeking a solution.
The results of the findings here will be detailed in other threads as they pertain to individual problems and the individual solutions addressed here can act as a database of reference.
If I'm the only contributor to this thread than so bee it, but it is hoped that we can pool our thoughts and minds collectively to arrive at solutions and suggestions resourcefully.
Let's dig in!
Geez also posted about this substances isolation in a thread
Post 492968
(geezmeister: "Strange flakes.", Stimulants)"I only saw these flakes once in the process, and they formed in alcohol and acetone-- and were insoluble in acetone when first removed and rinsed with acetone. This told me I had something in the mix I had not seen before, because I have not seen that crystal formation before. "
In a moment you'll all see why this one(or two) substance will precipate out in the two enviroments in which it was developed...Acetone and Isopropyl
EUDRAGIT® RL 12,5 / EUDRAGIT® RS 12,5
Solutions of EUDRAGIT® RL 100 or EUDRAGIT® RS 100, respectively, with 12.5% (w/w)
dry substance in a mixture of 60% (w/w) Isopropyl Alcohol Ph. Eur. / USP and 40% (w/w)
Acetone Ph. Eur. / NF.
Another substance(or two) is comprised of the chems polymers that are susceptable to release from mixtures when in contact with petroleum ether and sodium hydroxide
EUDRAGIT® RL 100 and EUDRAGIT® RS 100 are practically insoluble in petroleum ether,
1N sodium hydroxide and water. The polymer is precipitated from EUDRAGIT® RL 12,5 /
RS 12,5 when mixed with petroleum ether in a ratio of 1:1. When mixed with 1N sodium
hydroxide or water, the solution becomes cloudy or precipitates.
It's easily seen why this would hinder an A/B because of the mass it creates and may even encapsulate or prevent the amines movement from solutions containing this/these polymers.
For this second bunch creating this condition, Ibee proposes filtering the solids out of the basified solution before proceeding with the Nonpolar extraction. Rehitting these solids with another dose of dilute NaOh may result in maximizing the yield.
In the following extensive reviews and examples, the answers to separation and solubility will be addressed but the trick is going to bee in knowing which polymer is part of the matrix in the brand you started with.
You'll find some test methods and specifcations for this which should be of interest.
Hopefully some small tests can reveal that ID and based on the behavior of each, we'll develope workarounds from there.
As you'll see there are many different species here all with different behaviors and this one single name "Eudragit"(aka U`dashit...thanx foxy2 
) is only scratching the surface of what they are including. It could be siding with other unknowns to improve it's efficacy at hindering extraction further 
There are three main categories here:
•EUDRAGIT®
•EUPERGIT®
•PLASTOID®
and under each there are many subheadings...
We'll start with EUDRAGIT® first.
EUDRAGIT® polymers, are the favorite choice for solid oral formulations. They have become indispensable for the manufacture of enteric coatings on solid dosage forms, for sustained release formulations as well as immediate release coatings. New product developments for controlled release enable the use of most sophisticated coating processes and innovative drug delivery techniques to the benefit of our customers.
EUDRAGIT® L
EUDRAGIT® S
EUDRAGIT® NE
EUDRAGIT® RL
EUDRAGIT® RS
EUDRAGIT® E
There appears to be too main types here so I think it's worth defining what is "RL" and "RS" but I'll list them all....L-S-NE-RL-RS-E and let everybody derive their own conclusions...but we'll start with the tech specs first found in pdf files.
All that follow will be pdf files (I'll include file sizes for each) and screencaptured gifs that denote all the technical data on these polymers
First is
Eudragit® and Plastoid®-Residual Solvents
16.1 kB
•Standards Sheet
Specifications and test methods for
EUDRAGIT® RL 12,5 and EUDRAGIT ® RL 100
EUDRAGIT® RS 12,5 and EUDRAGIT ® RS 100
"Ammonio Methacrylate Copolymer, Type A and B" USP/NF
"Aminoalkylmethacrylate Copolymer RS" JPE
34.7 kB
Under this heading falls the Basic Information which is a 407kb PDF file for EUDRAGIT®
Enteric Coatings-pH Control with EUDRAGIT®
407.7 kB
Enteric Coatings – Product Overview
Here is the complete listing for
EUDRAGIT® Application Technology Sheetsin pdf format
Enteric coatings from organic solutions.
Tablets, coloured with EUDRAGIT® L/S.
23.8 kB
Enteric coatings with EUDRAGIT® L/S from organic solutions.
Tablets coated by fluid-bed process.
21.6 kB
Enteric coatings with EUDRAGIT® L/S from aqueous dispersions.
Tablets coated with redispersed EUDRAGIT® L/S 100.
104.0 kB
Enteric coatings with EUDRAGIT® L/S from aqueous dispersions.
Tablets coated with EUDRAGIT® L 30 D-55.
24.9 kB
Enteric coatings with EUDRAGIT® L/S from aqueous dispersions.
Active crystals coated with EUDRAGIT® L 30 D-55.
199.9 kB
Enteric coatings with EUDRAGIT® L/S from aqueous dispersions.
Tablets coated with redispersed EUDRAGIT® L 100-55.
27.5 kB
Enteric coatings with EUDRAGIT® L/S from aqueous dispersions.
Tablets coated with redispersed EUDRAGIT® S 100.
28.3 kB
Okay....that's it for the U`DaShit.
Boy...that was exhausting... 
Before I get my ass reamed for wasting bandwidth with this information, Ibee has reason to believe that the source may not be available once it's determined how this information may be used and felt it necessary to preserve it's existance and the integrity of it's content.
Sorry for length but it's only meant as a means of getting to the bottom of what is beeing dealt with and it's deep!
More will bee revealed!
Thank You to the Hive!
