[NormalPolymer]

Hi,

I think usually the sample is prepared by dissolving polymer in the solvent which is used in GPC column, but my polymer has bad solubility in the solvent used in the column. Is it ok to dissolve the polymer in another good solvent and then inject the solution into GPC column?
By the way, does anyone know what the polymer concentration is in the column? Suppose the concentration of injected solution is 1 mg/1 mL, injection volume is 0.1 mL, and the column flow rate is 1.0 mL/min.
THX a lot!

[marquis]

Can you say more about the system and the polymer you are using ( mobile phase, columns, detector, temperature used)?

I think you need to stay with the same solvent to dissolve the polymer as used in the mobile phase.  Sometimes, when you try to mix the two, you get the polymer precipitating out as soon as it hits the mobile phase at injection.  Not a good idea.
If you are using an RI detector, the difference in RI between the two solvents can overload the detector.  Your chromatogram will look very bad. 

Can you increase the temperature of your mobile phase to increase the solubility of the polymer?  Most of the instruments will allow your system to be heated above room temp.  You have to be careful with this.  THF is good to about 40 C, but going any higher is not a good idea. If you heat your system, it usually adds to the stability of your baseline.

Good luck.

[omermarwat]

Mixing of two solvents is not a good idea as it may damage your column, because the solvent for polymer should be the same as your mobile phase or any of your mobile phase from many solvent systems. You can also check the solubility of your polymer in that particular solvent via solubility parameters.