Page 1 of 1

GC-FID

Posted: Sun Oct 16, 2011 6:33 am
by mona_mh
HELLO guys
acording standard ASTM:D4747 i want to determine unreacted monomer content of latex(acrylic latex) by GC. BUT i've some problems,in procedure of this standard wrote: if the composition of the latex is not known, a preliminary analysis must be performed by diluting approximately 0.5g of latex with approximately 5g of warter ond injecting a 2microlitr into GC column.then by retention times to identify the monomers present. MY QUESTION IS:IS THIS SUSPENSION(0.5G OF LATEX + 0.5G OF WATER) DANGER FOR MY GC COLUMN? OR I HAVE TO FILTER THIS SUSPENSION? MAYBE IF I FILTER IT I'VE MANY ERRORS TO identify MONOMERS, my model of GC is:agilent 6890 N .
please help me.. thank you.
best regards.

Re: GC-FID

Posted: Mon Oct 17, 2011 8:32 pm
by dblux_
HELLO guys
... ond injecting a 2microlitr into GC column...
Hope it is not on-column injection but into the liner.
What type of injector is quoted in ASTM:D4747 ?

Re: GC-FID

Posted: Tue Oct 18, 2011 3:51 am
by Alexandre
Water injection is not a problem, assume it is with a good split. If you do not want to filter – centrifuge. Head space/SPME may be useful too.
------------------------
"If your experiment needs statistics, you ought to have done a better experiment." Rutherford

Re: GC-FID

Posted: Wed Oct 19, 2011 10:47 am
by gstaepels
You should check the volume of your liner and the volume 2 µl water takes at the injection temperature. I have an Agilent GC and the split/splitless liner has a volume of 900 µl. 2 µl water injected in an injection port at 250°C and a column head pressure of 100 kPa will give you a vapor volume of 1190 µl. In general you want no more than 2/3 of the liner volume as vapor. Under the above conditions the injection volume should be 0.5 µl maximum.

Re: GC-FID

Posted: Wed Oct 19, 2011 2:50 pm
by dblux_
In fact mona_mh is not afraid of water but rather of latex suspensed in water which was clearly articulated in capitals in her original post.