No - OX - Kapillare
No-Ox Tubing
Most HPLC installations use PTFE tubing as internal low-pressure transfer lines. PTFE is easy to use and chemically extremely inert. But most PTFE and PTFE alike polymers have micro pores which allow gases to penetrate freely.
  Therefore PTFE tubing is used in degassers as degassing membrane. By applying vaccum on the outside of the tubing, gases dissolved in solvents, passing through this tubing, will be removed. The solvent is degassed. A contrary effect can be observed when degassed solvent will pass through a PTFE tubing with standard air pressure on the outside. A ‘regassing’ will be observed, gases will penetrate through the PTFE tubing back into the newly and costly degassed solvent. We therefore created the No-Ox tubing. A FEP (PTFE like tubing) is coated on the outside with a PVDF tubing. FEP has excellent chemical resistance, but micro pores are present in the tubing wall. PVDF on the other hand is a very tight polymer, no micro pores can be observed, but it lacks chemical resistance. Coextruded No-Ox tubing will combine the two features of FEP and PVDF in the most positive manner, ensuring that degassed solvent will stay degassed until it reaches the HPLC pump. The PVDF-layer can easily be removed (using e.g. VICI Jour P/N 797 Clean-Cutter or razor blade) and stripped from the FEP so only Teflon will be immersed by solvent i.e. in the solvent reservoir. For connecting the No-Ox tubing we also designed a special KEL-F tubing insert (P/N 6141) to prevent solvent contact of the PVDF layer at the end when making connections. The ferrule inserts into the ID of the tubing and seals against the bottom of the port.
 SPECS:
 Material: FEP + PVDF
 Dimensions: OD 1/8", ID 1.65 mm
 Tolerances: +/- 0.05 mm (.002")
 Pressure rating: Low pressure only
 Special info: Be very careful when connecting our No-Ox tubing. Use the special designed KEL-F insert (P/N 6141) to prevent solvent contact of the PVDF layer.