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Rubber Lube

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sbmar

Marine/Ocean
Jan 1, 2005
26
I am doing a side project and know little to nothing about two chemicals that we are working with. I hope I came to the right place to get me on a track that will allow me to do some more testing.... My goal is to come up with a lubricant for a rubber impeller made of neoprene that operates in a very high friction environment and will heat up and fail quickly without something to lube it other than the water usually is pumping... We have chosen our base chemicals, propylene glycol and glycerin, as both of these seem to have what I think I want as to properties (relatively safe, water soluble, cheap, readily available, non-foaming, compatible w/ neoprene, etc) , and both seem to be in products like hair conditioner and some lotions which has the “lube” properties I need ( I have tested it) , but is inconsistent as to availability in quantity, changes viscosity a lot w/ temperature, and has a “girly smell” which I do not want—Plus I am hoping that I can make a product that cost less $$..............Please realize that this is not my language as my expertise lies a long ways from chemistry..

So, my current questions centered around glycerin and propylene glycol are:

~~Can they be mixed? Nothing stupid will happen, right??

~~When you add water to glycerin, does it really lower the freezing point? --- Seems weird--Add water to glycerin (up to a point) and it lowers the freeze point (?), and add water to glycol and it raises it (?)...

~~If we wanted a mix that would maintain a "multi-weight" viscosity from 120F to -30F (or even a bigger spread), what might be the best solution? What might I add to it?

~~Will the solution stayed mixed?

~~Can we add a color? Food coloring??

~~Do either of these chemicals or a mixture of them with "tap" or Reverse Osmosis water have a shelf life if kept in a clean bottle?

~~Is there a way to control the mix specs (just close) by volume instead of weight?

~~ I like the general “feel” of pure propylene glycol although it could be a touch “creamer”.. Tech grade glycerin is a little too heavy for me to work with, buy is quite slippery unless you add too much water... So, what might I used to add a creamier consistency without detracting from the “multi-weight” viscosity I need.—I’d like to maintain a relatively even thickness from about 120F down to 0F, or even a bigger spread---Or, I could have two solutions that would cover a wider range—+10F thru +140F and one for -40F thru +40F...something like that...

~~Since I need to use as little as possible of this lube over a 5-10 minute period (maybe an ounce a minute maximum) , we are looking for some “staying power”.....

Any ideas or help would be surely appreciated....We have the mechanics of the “delivery system” worked out, so now we are down to making the right “sauce”..............

Thanks, Tony



Tony Athens
 
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Aside from the two chemicals your are looking at you might want to look at the following chemicals. Both of these have been used for applications very similar to what you are trying to accomplish. Both can have excellent lubrication properties and Carbowax is an excellent film former.
I would get in touch with Dow and discuss your problem.

I have a bottle of Glycerin and water that's been in my shop for over thirty years, though it is not unusual for Glycerin to "spoil, mold" in bottles.

Polyox


Carbowax

 
Glycerine is a specific compound. You can dilute it, but it is what it it is.
Glycols on the other hand come in a wide vareity of types. You can start with ethylene or propylene glycols, Then you can talk about various molecular weights.
It might be easier for you to contact someone like JAX that specializes in food grade lubes.

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Rust never sleeps
Neither should your protection
 
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