residual monomers

[julia]

Hi,
We use an Agilent 6890 and I want to do the determination of residual unreacted monomer in a latex.

I want to recover those peaks : vinyl acetate, ethyl acrylate, methyl methacrylate, butyl acrylate, styrene and 2-ethylhexyl acrylate.


Now, we use a 7694 headspace sampler. We choosed to use a DB-WAX (PEG) capillary column 40.0m x 180µm x 0.30µm.

I have a problem to separate ethyl acrylate (BP 99.4°C) from methyl methacrylate (BP 101°C). Do you have any tips to give me? I tried to change the ramping temperatures, but it does not separate them enough.

Thanks

[chromatographer1]

An Agilent Gaspro capillary?

[julia]

An agilent capillary, but not Gaspro...

I tried many ramps to separate ethyl acrylate and methyl methacrylate, but in vain... I'm only able to separate them from 0.08 min. Is it normal?

[chromatographer1]

I would think the separation you describe is typical.

I still think the Gaspro column would separate them well. You could also try a Q PLOT capillary column. BUT, the styrene and larger analytes would not work well on that column.

The boiling point difference would not be enough to use methyl silicone either. You could try a Equity 1701 1µm 0.32mm capillary.

I have no other suggestions.

best wishes,

Rod

[julia]

Thanks a lot for your help!

[mahs]

hi

if you go for higher film thickness in capillary column , you may get got separation.