Melting Plunger. BB or MCT

[glaciershaker]

Ok I been brewing since about 2003. Using the standard 2/20 for years. Tried MCT oil for the first time. I using syringe filter PVDF .45 Whatman. My go to filter for years. I push with a 20cc syringe I made two 100cc batches. On the third push at 60cc both times the plunger started to melt. I've never had melt till MCT. I had melting issues using EO and never used since. Has anyone had a plunger melt using 20% BB? I haven't till MCT.

Ideas? Thanks in advance

GS

 

[XKawN]

Looks like a gel like substance at the tip of your syringe coming out?

 

[Dr JIM]

There is a chemical reason for what you're observing which is: "likes dissolve likes". In more specific terms that means the plunger and the oil are very similar chemically.

To uncover the problem you would need to KNOW what the chemical makeup of the PLUNGER and the OIL are EXACTLY

MCT is an abbreviation for what?

 

[Pincushion]

Had this happen when using 2/20 with mct when i used the same syringe to fill multiple vials. Try starting with a fresh syringe after every time you dump one. Also dont let the liquid sit for too long in the syringe. Small chunks of black rubber, no bueno

 

[Dr JIM]

MCT is an abbreviation for what?

Medium Chain Triglycerides such as; palm, kernel and coconut oil

The exact concentration may vary considerably depending upon the MCT manufacturer What is important, MCTs can react with and denature organic RUBBER, yet not silicone based polymers.

A couple options;
1) ensure the plunger is a PURE SILICONE polymer
2) use SCT or LCTs (short and long chain triglyceride)

Problems inherent to # 2, longer chain AAS esters (8-9 carbon chain or more) are less soluble in SCT solvents and LCTs have a tendency to solidify at "room temperatures".

I suspect the latter "problems" was the rationale for using MCT, it solubilizes the Decanoate and UnDecanoate AAS esters quite readily.

BEST OPTION……. use a PURELY SILICONE BASED POLYMER PLUNGER.

Good luck

 

[glaciershaker]

Yes PIN. That's just what happen. I pushed 40 no problem then on the start of the next 20cc's I saw pieces floating. Strange. I have some test e that I'll brew without BB and just BA and MCT and see how that goes. It didn't sit long at all. As soon as I filled the syringe it was on the filter and going in.