Sciencemadness Discussion Board

Super Lube synthetic grease as ground glass lube

thewanderer - 22-2-2013 at 15:23

Hello,

Long time reader, first post. Love the forum, tons of info! I've been doing various experiments for some time but have recently acquired some glassware (mainly a vacuum distillation set) to do some more culinary type stuff: distilling spice/plant oils, make rosewater, etc.

The distillation set has ground glass joints, something I've not really used before. I've read various recommendations on here (petroleum jelly, teflon tape, dielectric silicone grease from the auto store, etc) as far as lubing the glass joints. I picked up an inexpensive 3 oz tube of "Super Lube" the other day, as I couldn't find the one silicone dielectric grease mentioned on another thread here.

Super Lube MSDS is a link to the MSDS, essentially it's <85% polyalphaolefin, <25% petroleum, <5% fumed silica, <4% PTFE, <2% antioxidant, <1% polyglycol, and <0.5% polyisobutylene. Their site claims "Super Lube® is Food Grade, rated H-1 by the USDA and NSF for incidental food contact. It is an excellent Dielectric and operates over a temperature range from -45° to 450° F. "

Has anyone used this as a joint lubricant? It is non-toxic and USDA/NSF food grade, but would I be better served using something else since this will be for food related work?

Mailinmypocket - 22-2-2013 at 15:57

I haven't used that specific dielectric grease, but I use this one all the time:

http://www.permatex.com/products/product-categories/speciali...

Works like a charm, except for the rare occasions that I use conc. H2SO4 instead.

phlogiston - 22-2-2013 at 16:20

Do you intend to eat your products?
If so, taste and toxicity are ofcourse important concerns, and the greases that are commonly used for this purpose may not be so suitable for you.

watson.fawkes - 22-2-2013 at 17:05

I'd recommend using a saturated fat. These fats include coconut oil, palm kernel oil, beef tallow, and pork lard. They are already food, and so you won't have to worry about what's in them.

The advantage is that they are solid at room temperature. You can apply them by rubbing, an easy way to avoid applying too much and having it contaminate your product. Cast yourself an application stick directly into a lip balm dispenser; use an old one or buy new (e.g. from Amazon).

thewanderer - 23-2-2013 at 11:09

After reading a bit more on this Super Lube, it definitely seems like it'd fit the bill: since it is an NSF H-1 lubricant, it means it's fine for use where it comes in contact with food (as opposed to H-2 grade that can be used on food equipment, but only where there is no possibility of food contact) It is also apparently used on potable water/steam line gaskets as well as moving parts inside food ovens.

Quote: Originally posted by phlogiston  
Do you intend to eat your products?
If so, taste and toxicity are ofcourse important concerns, and the greases that are commonly used for this purpose may not be so suitable for you.


Yes, I'd intend on consuming the product- if it turns out! Some of my other hobbies include making beer, cider, and cheese and I've been wanting to try extracting flavors to add to these.
Quote: Originally posted by watson.fawkes  
I'd recommend using a saturated fat. These fats include coconut oil, palm kernel oil, beef tallow, and pork lard. They are already food, and so you won't have to worry about what's in them.

The advantage is that they are solid at room temperature. You can apply them by rubbing, an easy way to avoid applying too much and having it contaminate your product. Cast yourself an application stick directly into a lip balm dispenser; use an old one or buy new (e.g. from Amazon).


Neat idea... I didn't even think of using fats. I like the lip balm applicator idea as well. The only issue I see is all of those have a melting point in the 30-45° C range. Do you think at 100° C, the fat would seep out of the joints leaving them stuck together?

phlogiston - 23-2-2013 at 14:27

No, capilary action will retain it. You only need an infinitesimally thin film, just enough to make the joint look clear instead of white.
Two other options:

1. vaseline works and it has almost no taste or smell, decomposition temp is >350 deg. Make sure to get the purified vaseline that is for instance used as lip balm.
(the stuff sold in hardware stores for lubrication can contain unhealthy impurities).

2. Teflon tape, as for instance used by plumbers. Inert, easily available, heat resistant and non-toxic. However, it does take a little practice to make a perfect seal especially if you want to pull a vacuum.

Hexavalent - 23-2-2013 at 14:48

I have always used, and probably will always use, ordinary vaseline sold as a lip balm: here in the UK, I can get a kilogram of it for ~£3 and I load some into a 20 mL syringe for easy dispensing.