Bottle Caps for Freezing Nic

[Boletus]

I have some 120 ml glass bottles left over from work that I want to use to freeze some nic base. However, the caps are not the usual type. They are designed to contain samples of volatile materials. The liner of the cap is a polytetrafluoroethylene (PTFE) faced silicone septa that can be tightened to form a vapor lock within the vial, and the outside center of the cap is a soft, rubber-like material (septum) that allows the lab to insert a syringe needle without removing the cap (see photo). As such, they provide a good barrier to to vapor exchange, at least in the short term, but I am not sure how well they will hold up to freezing. Does anyone know if these caps can be used for freezing?




[edit] I found a website that explains the thread terminology. In case others are curious, this provides a pretty good summary: SKS Bottle - Cap & Neck Finishes [end edit]

Barring that, can anyone explain the cap thread terminology so I could determine how to order the correct replacement caps without resorting to simple trial and error? I see terms like "22-400 continuous thread neck finish" used to describe thread types at Packaging Options Direct, so I am wondering what the "22-400" signifies.

 

[Nermal]

Interesting idea. I'll help you wait for an answer.

 

[RobertNC]

Those syringe type caps do not seal all that well, despite the fact that they are widely used in medical settings.

I would recommend you replace them with solid caps that have PTFE liners, then also after capping tightly wrap the outside edge heavily with plumbers tape which is also simply PTFE film. Look for the Green polymer caps with PTFE liners. It may be somewhat difficult to find just the caps, at some point in the FDA timeline I also plan on stockpiling a bunch of nicotine but will need glass bottles as well. Bottles with green polymer/PTFE lined caps are widely available on Amazon.com, I suggest that as a logical place to start looking for just caps as well.

 

[dannyv45]

Here's a good place to get caps. I recommend the poly seal caps.

Results for Caps & Closures

 

[RobertNC]

[edit] I found a website that explains the thread terminology. In case others are curious, this provides a pretty good summary: SKS Bottle - Cap & Neck Finishes [end edit]

Another good source of info is Qorpak - they are the leader in the medical and chemical industries. I strongly recommend the F217 PTFE/Green thermoset caps for long term cold storage of e.g. nicotine base.

Cap Material & Liner Descriptions | Qorpak