Mixing polar and non-polar base fluids

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If you're mixing polar and non-polar base fluid, the first for additive solubility, does that mean the additives stay mainly in the polar component of the finished fluid? If that polarity also makes the polar fluid (and additves with them) attracted to metal surfaces, does that mean you get a higher additive concentration at those surfaces?

Are Viscosity Index Improvers also dependant on the solvency of the base fluids?
 
Originally Posted By: Jetronic
If you're mixing polar and non-polar base fluid, the first for additive solubility, does that mean the additives stay mainly in the polar component of the finished fluid? If that polarity also makes the polar fluid (and additves with them) attracted to metal surfaces, does that mean you get a higher additive concentration at those surfaces?

Are Viscosity Index Improvers also dependant on the solvency of the base fluids?


Much depends on the type of non-polar base oils.

For example - if you have an AN or an ester of at least 10% total volume and are mixing with a PAO the whole solution should be amenable to solving additives.

Now, if using an OSP you are going to need way more solving ester or AN than with PAO.

One thing you're forgetting is that most additive packages are polar solvent themselves.

Many additive packages or the components within the additive packages are themselves esters or have polar solvents within.
 
Way more, how much? I had 20%OSP mixed with cheap semi synthetic and it phase separated, over some time. I could see the density line right there. OSP isn't that much soluble or the addpack originally on the semi syn unpacked and separated the from the mineral part and migrated?
 
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It depends on the OSP's viscosity. The lower viscosities have better solvency then the higher viscosities.
 
Originally Posted By: Jetronic
Are Viscosity Index Improvers also dependant on the solvency of the base fluids?

VI improvers usually have very good solubility with mineral, PAO and ester base oils. They typically have a large percentage of group I or group II base oil as a carrier fluid which makes them very easily miscible with most other fluids.
 
Originally Posted By: Jetronic
If you're mixing polar and non-polar base fluid, the first for additive solubility, does that mean the additives stay mainly in the polar component of the finished fluid? If that polarity also makes the polar fluid (and additves with them) attracted to metal surfaces, does that mean you get a higher additive concentration at those surfaces?
My understanding of it goes like this and I'm not saying it is absolutely correct because I've never thought about it before to research it thoroughly:

Once the base oil/additive mixture is in solution there are not really distinct separations. So what you get on the metal surface is representative of the entire fluid. It's not as if the polar components are drawn from the bulk of the oil to the surfaces. The polar component simply increases the overall polarity of the entire mixture which is then drawn to the surfaces since it can not be separated at that point.

Although What you are asking about the additives being sort of "tied" to the polar base fluids is valid because certain additives should be mixed into a polar component before being added to low solubility base oils to avoid separation. I've seen this firsthand when blending. However once that mixture is then added to the rest of the formula I don't think a distinction can be made after that point simply because the additive and polar base fluid are so uniformly distributed.
 
However there is a problem with competing for surface. This is why additive packages are a careful balance of different components. Too much rust inhibitor too little wear protection. The number one cause of problems with after-market additives. They can upset the balance and other properties suffer.
 
Originally Posted By: MotoTribologist
Originally Posted By: Jetronic
If you're mixing polar and non-polar base fluid, the first for additive solubility, does that mean the additives stay mainly in the polar component of the finished fluid? If that polarity also makes the polar fluid (and additves with them) attracted to metal surfaces, does that mean you get a higher additive concentration at those surfaces?
My understanding of it goes like this and I'm not saying it is absolutely correct because I've never thought about it before to research it thoroughly:

Once the base oil/additive mixture is in solution there are not really distinct separations. So what you get on the metal surface is representative of the entire fluid. It's not as if the polar components are drawn from the bulk of the oil to the surfaces. The polar component simply increases the overall polarity of the entire mixture which is then drawn to the surfaces since it can not be separated at that point.

Although What you are asking about the additives being sort of "tied" to the polar base fluids is valid because certain additives should be mixed into a polar component before being added to low solubility base oils to avoid separation. I've seen this firsthand when blending. However once that mixture is then added to the rest of the formula I don't think a distinction can be made after that point simply because the additive and polar base fluid are so uniformly distributed.


The so called smart molecules are marketing nonsense. If you drain the oil, the polar fractions won't get behind the bulk attached to metal parts.
 
Originally Posted By: Ohle_Manezzini
Originally Posted By: MotoTribologist
Originally Posted By: Jetronic
If you're mixing polar and non-polar base fluid, the first for additive solubility, does that mean the additives stay mainly in the polar component of the finished fluid? If that polarity also makes the polar fluid (and additves with them) attracted to metal surfaces, does that mean you get a higher additive concentration at those surfaces?
My understanding of it goes like this and I'm not saying it is absolutely correct because I've never thought about it before to research it thoroughly:

Once the base oil/additive mixture is in solution there are not really distinct separations. So what you get on the metal surface is representative of the entire fluid. It's not as if the polar components are drawn from the bulk of the oil to the surfaces. The polar component simply increases the overall polarity of the entire mixture which is then drawn to the surfaces since it can not be separated at that point.

Although What you are asking about the additives being sort of "tied" to the polar base fluids is valid because certain additives should be mixed into a polar component before being added to low solubility base oils to avoid separation. I've seen this firsthand when blending. However once that mixture is then added to the rest of the formula I don't think a distinction can be made after that point simply because the additive and polar base fluid are so uniformly distributed.


The so called smart molecules are marketing nonsense. If you drain the oil, the polar fractions won't get behind the bulk attached to metal parts.

Precisely
thumbsup2.gif
 
I had dinner with a chemist involved in the Castrol "UMA" when it was confined to 10W40 grades here in Oz.

He was no longer Castrol, and was with an independent re-refiner, but he DID state that the Magnatec effect carried through the oil changes.

Routine was
* Mobil 1 baseline
* low additive flushing oil
* Magnatec
* flushing oil
* Mobil 1 to bookend the test.

The effect of the UMA lasted through the flushing oil and into the next M1 run.
 
All the papers I've seen of AN and other polar fluids mixed with non-polar, show that you get a much larger than linearly expected benefit. This can only happen if the polar molecules concentrate around the metal surfaces.
 
Originally Posted By: Shannow
I had dinner with a chemist involved in the Castrol "UMA" when it was confined to 10W40 grades here in Oz.

He was no longer Castrol, and was with an independent re-refiner, but he DID state that the Magnatec effect carried through the oil changes.

Routine was
* Mobil 1 baseline
* low additive flushing oil
* Magnatec
* flushing oil
* Mobil 1 to bookend the test.

The effect of the UMA lasted through the flushing oil and into the next M1 run.


Effects, like? From witch component? I am curious now.
 
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Polar vs non polar .if you don't have a means to keep thing different at one point both will reach equilibrium yep it means when vehicule isn't running the opposite of what is happening when the car is run should occur so when the car is running you always get the desired effect
 
Shannow's friction reduction during mixed & boundary: Might indicate competition for surface which could happen by mixing (OK, blending) FM'd PCMO with non-FM'd HDEO?
 
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