Yes, both are soluble in water and lower alcohols (methanol, ethanol, propanol).

Thanks for your reply. I should prove that PEGDME dissolves in ethanol and water.Maybe I can do it by solubility parameters.Do you have solubility parameters for polyethylene glycol dimethyl ether(PEGDME) and ethanol?

Regrets :-( I havn't

So by your own experience you know that PEGDME is soluble in ethanol and water?Cause for my PhD thesis I should ensure.Thanks again.

PEG 300 is freely soluble in water, PEG 1000 - 750g/L, then drop slowly by mass increasing to 500g/l for PEG 20000. End-cupping with Me-group influence slightly for low molecular PEG, for high molecular mass polymer solubility is identical.

From Wiki http://en.wikipedia.org/wiki/Polyethylene_glycol :

"PEG is soluble in water, methanol, ethanol, acetonitrile, benzene, and dichloromethane, and is insoluble in diethyl ether and hexane." -

Some solvents for PEG are present in MSDS from http://www.scientificpolymer.com/catalog/prod.asp?ProductType=Polymer&Alpha=&ScrollAction=12

As I see from pebax.com , PEBAX is very interesting polymer !

Dear Tayebe,

EtOH is antisolvent vor PEBA, and water is also naturally - check attached file.

Mixture (3:1) of 1-propanol /1-butanol (80oC) seems to be suitable for mixing with PEG and its derivatives.

I'd seen this document before but many other researchers used ethanol+water as solvent. The Pebax solution has a tendency to gellify and using ethanol+water as solvent prevents it.I've experienced it and it works.What I'm affraid is that terminal groups of PEGDME (methyl groups) make a problem (because PEG has -OH terminal groups which make a hydrogen bonding by alcohol and water molecules). Althogh I know that PEGMDE because of ether groups is polar and cosequenty dissolves in polar solvents but I worry about methyl terminal groups...

Thanks, Tayebe, it is very interesting for me - to dissolve PEBA in EtOH/H2O! Can you tell me what type of PEBAX (catalog number of ARKEMA or chemical composition) have you used, and temperature? Since original publication in 1999, may be some new types of PEBAX was developed.

About solubility of PEGMDE - from my hands-on experience, CH3OCH2CH2OCH3,

CH3O-CH2CH2O-CH2CH2O-OCH3 and CH3OCH2CH2OCH2CH2OCH2CH2OCH3 - all of this ethers have limitless miscibility with water, like to corresponding alcohols. And hydrogen bonding is also assigned to ether oxygen - from hydrogen of water and in PEBAX from (- CO-NH-)-fragment - -N-H...OR2). As you may be know, diethyl ether have appreciable solubility in water, in contrary to pentane that have -CH2- on place of -O- .

Dear Andrei, thanks for your kind help,

I've used "Pebax MH 1657" and it dissolves in ethanol+water at about 80˚C under reflux.

Yes Polyethylene glycol dimethyl ether (PEGDME) dissolve in both water and alcohols

Dear Tayebe, thanks a lot for pdf ! "Pebax MH 1657" is 60% PEG (!) polymer.

I think that you work in area of gas purification, so attached file may be useful. It is known that polypropylene and polyethylene carbonate are very good solvents used in CO2 absorption. Its polymer analogs may have also such properties - as additives to PEBAX, or self-contained with low-molecular PEG or better polypropyleneglycol additives as plasticizer

Thank you dear Andrei for explanation and PDF.

should dissolve in alcohol......PEG is used a lot in ceramic powder pre-preparation procedures,,,,,

Should be able to form hydrogen bonds with both alcohols & water, so should be able to dissolve.

Calculated Hansen SP of PEGDME model compound (low MW):

-- Hansen's 3-D solubility parameters (delta/sqr(MPa)) -empirical:

-- dispersion = 19.8688

-- polarity = 3.84836

-- hydrogen bonding = 12.6901

-- solubility parameter = 23.8877

Solubility Parameters of ethanol:

-- Hansen's 3-D solubility parameters (delta/sqr(MPa)) -empirical:

-- dispersion = 15.7607

-- polarity = 8.80342

-- hydrogen bonding = 19.3925

-- solubility parameter = 26.4947

You can calculate the radius of interactions between the 2 and if it is less than about 4.88 then the polymer should dissolve. The lower the value the more compatible. It does not tell the extent of solubility or how fast it will dissolve. In this case, your calculations should give about 12 so ethanol is not a good solvent.

I did this quickly so please check calculations.

I really do not understand the whole lengthy discussion. Would have been faster mixing the Me-end-capped PEG with water, ethanol and observe full or limited miscibility. Yes should dissolve in both.

Just one more note about this:

Here is a reference for isopropanol and other solvents.. This is not simple system, solubility varies with T and MW.

Solubility, crystallization and oiling-out behavior of PEGDME:

1. Pure-solvent systems

Kai Kiesow, Feelly Ruether∗, Gabriele Sadowski

Laboratory of Thermodynamics, Department of Biochemical and Chemical Engineering, Technische Universitaet Dortmund, Emil-Figge-Str. 70, 44227 Dortmund, Germany