bleeding and shrinkage of Hayesep P

[Daniel-HH]

Hello all,

I've big problems using a Hayesep P column.
I'm using a micropacked column with Hayesep P as packing material. Hayesep P has a maximum temperature limit of 250°C.
While analysing I ramp up the column temperature from 70°C up to 200°C. After a few hundred cylcles a see small particles and a kind of small liquid drops in the transfer line from the column to the TCD. I also see a shrinking of Hayesep material.
What could be the reason for the bleeding? The temperature? Or should I make some additional conditioning steps before packing?

Thanks,
Daniel

[chromatographer1]

Did you pack this column yourself or buy it from Hayes, or a third party?

VICI now owns Hayesep manufacturing (Mr. Hayes died some years ago) and even while he and his son manufactured the material in latter years there were lots where the packing was not always cleaned and dried to my satisfaction due to the scaleup of manufacturing as their packing sold so well.

Now that this manufacturing has passed on to VICI, I do not know how well it is presently cleaned after polymerization. One can have styrene or the other monomer elute from the packing. If you condition the packing before it is cleaned properly you can have blockages in the bead channels and excessive shrinking.

I personally developed a cleaning, drying, and packing process for a company that solved these issues to a high degree in manufacturing packed columns, but it is necessary that you insist your column is packed with precleaned support if you desire the best possible column. This may add 30-50% to the price of the column (a guess on my part, maybe less, maybe more) and a delay of a week or more in shipping.

You SHOULD NOT SEE condensation of liquid after conditioning a packed Hayesep column.

This process is proprietary (company intellectual property) and I regret it would be inappropriate for me to tell you how to do it yourself, and about the problems with doing it well.

I can tell you that you will crosslink between beads if you heat them at elevated temperatures and gaps will occur (void spaces in the packing) which can cause tailing and poor peak symmetry. This is minimized by properly preparing the support before packing the column.

best wishes,

Rod

[Daniel-HH]

I packed the columns myself. The column itself is silicon-glass-chip with etched channels with an inner diameter of 0.3mm (300µm).

While packing I use Acetone to reduce the eletrostatic forces between the beads.

After packing I glue in the fused-silica capillaries and then I build in the column into the GC and start measuring.

Ok, I will make a cleaning and conditioning step next time before packing.

By the way: With Hayesep A everything work perfect.

Thanx,
Daniel

[chromatographer1]

that is called batch to batch variation.

best wishes,

Rod

[alabsiam]

that is called batch to batch variation.

best wishes,

Rod

Hello Rod !

Can you help me? my post topic is "Need your help & clarification in calculation of GCMS result"