Cap and septa assemblies

Part number: J208-1201193100

Image is representative (may not be specific item).

Cap 8 mm smooth black polypropylene screw cap
Liner White silicone/red PTFE 1 mm thick septa
Description 8 mm smooth black polypropylene screw cap with white silicone/red PTFE 1 mm thick septa PK100

Septa, caps and liners play a key role in the storage and preparation of samples. They securely seal samples from the external environment while simultaneously allowing injection by sampling needles.

Features and benefits

  • Pre-assembled caps and septa reduce handling and therefore contamination.
  • Custom color combinations, materials, and geometries available upon request.
  • Aluminum crimp caps provide a leak-resistant seal.
  • Use of a crimping tool is required for aluminum seals.
  • Magnetic crimp seals for use with autosamplers.
  • Snap caps are easy to apply and remove without tools, eliminating the need for crimping tools.

Recommended applications

Cap types

Crimp caps

  • Crimp caps provide extra security for studies where it is important to avoid contamination or sample tampering.
  • Can become rounded when crimped onto a vial, resulting in less surface area for magnets to stick to during automation.
  • Require crimper/decrimper, can cause septa distortion if overcrimped.

Screw caps

  • Often used for LC and LC/MS.
  • Provide an airtight seal.
  • For automation, magnetic screw caps are advantageous because they are less likely to become rounded over time, providing increased surface area for the magnets used to move the vials.
  • This decreases the risk of any vials falling from the magnet.

Snap caps

  • Simple snap design when crimping tool is not available.
  • Easy removal without special tools.

Septa suitability with chemicals
The table below summarizes the suitability of each septa material with a range of chemicals, this can vary based on factors such as temperature, molecular weight and solvent concentration.

Filter by chemical:

 

PTFE

PTFE/silicone

PTFE/silicone/PTFE

Viton

Silicone

Silicone/FEP

Silicone/polyimide

Butyl

Foam (PTFE/polyethene foam)

Acetonitrile

 

 

Hydrocarbons

 

 

 

Methanol

 

Benzene

 

 

 

THF

 

 

 

 

Toluene

 

 

 

 

DMF

 

DMSO

 

 

 

Ether

 

 

 

DCM

 

 

 

Alcohols (ethanol)

Acetic acid

 

Acetone

 

Phenol

 

 

Cyclohexane

 

 

 

 

Septa compatibility with applications
This table provides a summary of the suitability of our septa materials to a variety of applications.

 

PTFE

PTFE/silicone

PTFE/silicone/PTFE

Viton

Silicone

Silicone/FEP

Silicone/polyimide

Butyl

Natural rubber

Temperature range

Up to 260°C

-40°C to 250°C

-40°C to 250°C

-40°C to 260°C

-40°C to 250°C

-40°C to 250°C

-40°C to 300°C

-50°C to 150°C

0°C to 90°C

Multiple injections

No

Yes

Yes

No

Yes

Yes

Yes

No

No

Price

Very economical

Economical

Most expensive

Economical

Very economical

Economical

Expensive

Economical

Most economical

Suitable for storage

No

Yes

Yes

No

Yes

Yes

Yes

No

Yes

Best for

  • Superior chemical inertness
  • Single injections
  • Short cycle times
  • Most common HPLC and GC analyses
  • Not suitable for chlorosilanes
  • Ultra analysis
  • Repeat injections
  • Internal standards
  • Chlorinated solvents
  • High temperatures
  • Limited resealing, not suitable for multiple injections
  • General purpose
  • Highest chemical compatibility
  • Sample sensitive to PTFE exposure
  • High temperature
  • Organic solvents
  • Acetic acids
  • Impermeable to gases
  • General GC applications
  • Limited resealability

Product specifications

  • Cap types: Crimp, screw, snap, cap.
  • Cap materials: Polypropylene, aluminum, tin/steel/nickel coated, bimetal, phenolic.
  • Septa liner and film materials: Silicone, silicone with PTFE, silicone with polyimide, silicone with FEP, butyl, foam, viton.
  • Septa thickness range: 0.25 mm to 4 mm.
  • Septa configurations: Non slit, straight slit, star slit, cross slit, Y-cut, step slit, washer.

More

Please refer to the brochure (includes part number lists) for more items.