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Informacje na temat estrow oraz ogolna wiedza - Na pytania odpowie Thomas Schaefer (TomNJ)

  • Thread starter Deleted member 925788
  • Start date
We only made esters. We tested esters for elastomer compatibility back in the 70s when we developed ester based motor oils, but not since unless required by a specification, such as for jet engine oils.
 
@TomNJ Sometimes I hear opinions that PAOs can shrink old elastomers. But there are, after all, suitable additives (e.g. with a carboxyl group) that make all types of elastomers swell. But it's also a question of compatibility, in my opinion, when the seals are old, they leak, you just have to replace them. There are components. Have you ever known that there was a leak after switching to fully synthetic PAO oil? I personally don't. For example, on the forum we have the user @Zielony34 , who used only PAO-based oils for ca. 50kkm, everything tight.
 
Pure PAO can shrink and harden some elastomers, but we do not run engines on pure PAO. Formulations high in PAO contain seal swell agents to counter the effect of the PAO. Esters have traditionally been used for this purpose but other chemistries are also used.
 
@TomNJ
In the German oil club it is said that PAO is shrinking the seals. It is not stated that oils with a high PAO content contain protective substances. But there are no pure PAO oils for engines.
Meguin Megol Super Leichtlauf 5W40 has a lot of PAO (analyzes are known: Meguin Megol Super Leichtlauf 5W-40) and it is said that this is bad for the "old" seals. They do not say what is "old" and thus scare users of leaks.
You can read it here:

Dichtungen/Elastomere - PAO und Ester verträglich ?? - Ölanalysen und Ölanalytik für Motor und Getriebe

Hier Interessante Links : Link [URL:http://www.molyduval.com/index.php?module=explorer&displayAction=download&downloadFile=datenblaetter_cd/de/cat/dichtungen.pdf] Elastomere Beständigkeit…
oil-club.de oil-club.de
especially from here:

Ölanalysen und Ölanalytik für Motor und Getriebe

Diskussionsforum: Ölanalysen und Ölanalytik für Motor und Getriebe
oil-club.de oil-club.de

Ölanalysen und Ölanalytik für Motor und Getriebe

Diskussionsforum: Ölanalysen und Ölanalytik für Motor und Getriebe
oil-club.de oil-club.de
>>> Here the fully synthetic PAO (Ravenol VSW) is said to have leaked with an ester. But it is said that Ester supposedly has protective properties.

What should I believe.
What technology is behind it?


The sad thing is, that missing Ester in an oil is a reason in the German Oil-Club to say that the oil may be a risk for the seal.
Seal swell agents can not be detectet in an analyze, so they thik there ist noting in to safe the seal.
 
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Most if not all oil specifications include specifications for the swelling and tensile strength of a variety of elastomer seals. It is up to the formulator to select ingredients that will allow the finished oil to meet these specifications. If they use high concentrations of PAO or ester, then they must balance the seal effects with other base oils or with additives. Seal swell additives are generally organic and usually do not show up in metal or FTIR analysis. If you choose a reputable oil brand and the oil meets the specifications for your engine, you should not have to worry about leakage caused by the oil.
 
The proper name for POEs is "Neopentyl polyol esters" because they all have a neopentyl molecular structure in the alcohol portion, that is four carbons bonded to a center carbon. This structure eliminates beta hydrogens and increases the stability of the ester.

A major type of neopentyl polyol alcohols used to make POEs is pentaerythritol. This is usually abbreviated as "PE" and esters made from it are called "PE esters". They are commonly used in jet engine oils, refrigeration oils, and other industrial oils and greases. There are different grades of PE available, and the most pure grade is often referred to as "monopentaerythritol", abbreviated as MPE. A slightly less pure version but equally stable is referred to as "technical pentaerythritol" and abbreviated as TPE. Two PE molecules connected by an ether linkage is called dipentaerythritol and abbreviated as DiPE.

It appears the ester you are referring to is a polyol ester made from MPE. These are excellent products and there are many different types depending on which acids are used to make the esters. For more information, see my paper on esters here:

Esters in Synthetic Lubricants
 
If you are referring to Nycobase 7450, that ester appears to have a high dose of C5 acid, which I would avoid for motor oil formulations. Nycobase 8103 would be a better choice.
 
Hi @TomNJ I forgot to ask you, what is your opinion on GTL? Despite the disadvantages such as high aniline point, etc., many chemists appreciate more than group IV oils.

Interesting patent below.
 

Attachments

  • WO2008055976A2.pdf
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@TomNJ
If we are talking about GTL, did you hear users opinion, that oils based on GTL, shows increased consumption?
I'm talking about Shell Helix Ultra mainly.
I dont know how to verify this phenomenon.
Oils are characterized by low NOACK values.
 
@TomNJ You tested the lubricants for Hildebrand Solubility Parameter or Kauri-Butanol Value ?
 
Good evening,

This topic is really interesting:

TomNJ napisał:
In general, modern tribology brings better additives and base oils than old formulations and should be suitable for older engines along with the right viscosity grade. If I could not find any oil recommendations from my engine manufacture, then I would lean toward a thicker oil in old engines, such as 10W-40, or 5W-40 if cold starting is a factor.
Click to expand...

So, can we use modern synthetic oils in older and old engines (constructed in 90s or a bit earlier) without contraindicates (obviously if engine is in good condition) to help them to retain the best condition for years ? I mean mostly real synthetics oils made from PAO plus esters.

I would like you to ask the question from other news: does the oil with significant amount of esters (mostly oils for more agressive engine treatment, but I don't mean pure motorsport oils) can lose faster their properties that conventional ones especially, when using on short distances in the city ?
 
SACZI napisał:
[USER = 1304] @TomNJ [/ USER]
If we are talking about GTL, did you hear users opinion, that oils based on GTL, shows increased consumption?
I'm talking about Shell Helix Ultra mainly.
I dont know how to verify this phenomenon.
Oils are characterized by low NOACK values.
Click to expand...
I cannot think of a technical reason why GTL based oils should show increased oil consumption. Increased consumption is sometimes a mystery and sometimes noted when just changing brands.
Post automatically merged:

poziom1989 napisał:
[USER = 1304] @TomNJ [/ USER] You tested the lubricants for Hildebrand Solubility Parameter or Kauri-Butanol Value?
Click to expand...
No we never ran these tests.
Post automatically merged:

Limonka napisał:
Good evening,

This topic is really interesting:



So, can we use modern synthetic oils in older and old engines (constructed in 90s or a bit earlier) without contraindicates (obviously if engine is in good condition) to help them to retain the best condition for years? I mean mostly real synthetics oils made from PAO plus esters.

I would like you to ask the question from other news: does the oil with significant amount of esters (mostly oils for more agressive engine treatment, but I don't mean pure motorsport oils) can lose faster their properties that conventional ones especially, when using on short distances in the city?
Click to expand...
Lose what properties?
 
TomNJ napisał:
Lose what properties?
Click to expand...
Well, I guess the concentration of esters can be within following range: 8% up to 15% (assuming by available VOAs). I mean oils like Amsoil Signature Series, Millers Oils CFS series or/and Penrite Racing. To be honest the last ones are the main point of my interest, because they have higher ZnDDP level, which can be desired by older and old engines.
 
@TomNJ Have you tested different antioxidants? Which did you think worked best? Based on research, the amine antioxidant stands out.

Or is it best to find a balance, use a phenolic / amine antioxidant mix and the appropriate Mo compound and the classic ZnDDP?
 
@TomNJ
TomNJ napisał:
Lose what properties?
Click to expand...
I need to somehow clarify my question: well for me as I am not a chemistry specialist it is difficult to say exactly what these properties shold look like :( I have read somehow in the internet that these strenghten motor oils can degrade a bit quicker that rather conventional synthetic oils when using also in the cities. It can be true or maybe these oils can protect even better engine in this mixed working conditions (driving in cities and long routes) ?
 
poziom1989 napisał:
[USER = 1304] @TomNJ [/ USER] Have you tested different antioxidants? Which did you think worked best? Based on research, the amine antioxidant stands out.

Or is it best to find a balance, use a phenolic / amine antioxidant mix and the appropriate Mo compound and the classic ZnDDP?
Click to expand...
I did extensive work with various anti-oxidants, but only in esters, mostly POEs. In esters we found amine types most effective, although we did use a mix of amine and phenolic types in a couple of products. Jet engine oils, which are 95% POE, use only amine AOs, usually two different ones to exploit synergies. I believe phenolics are more commonly used in hydrocarbon based oils, but I am not sure if the reason is performance or cost.
Post automatically merged:

Limonka napisał:
[USER = 1304] @TomNJ [/ USER]

I need to somehow clarify my question: well for me as I am not a chemistry specialist it is difficult to say exactly what these properties shold look like :( I have read somehow in the internet that these strenghten motor oils can degrade a bit quicker that rather conventional synthetic oils when using also in the cities. It can be true or maybe these oils can protect even better engine in this mixed working conditions (driving in cities and long routes)?
Click to expand...
I would not have any problem using modern synthetic oils in older engines from the 90s. And I would not expect oils containing esters to lose performance in short trip service.
 
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