Softening old hardened rubber.

[jon haney]

59 minutes ago, SwampNut said:

 

But this is why I commented that people would read and SDS or two; you learn so much, and it could change your life.

 

I agree.  However, I did have a customer ask me for SDS on 304 stainless steel sheet metal. 🤪  Not sure what he would learn from that, other then we had none.

It seems like most of the time when I read SDS at work, I can't find the info I'm looking for.

[SwampNut]

Hmm, would the ingestion hazard on that be swallowing or Keistering?

 

[XXitanium]

Good thing you don't live in California!

 

I'm looking for mySAFETY DATA SHEET - Fisher Scientific https://www.fishersci.com/store/msds?partNumber=AA43301&productDescription=keyword&vendorId=VN00024248&countryCode=US&language=en

 

[superhawk996]

11 hours ago, SwampNut said:

 

Looking at the SDS for Methyl 2-hydroxybenzoate says it's pretty damn volatile with a vapor pressure of 13, boiling temp of 222.  But it will be trapped inside the rubber which changes things.  This is a great question and hopefully Oscar will love the R5 enough to report in a couple years.  I suspect that trapped in the rubber, it will behave like most oils and be pretty stable.

Early on I was shocked at how fast it seemed to evaporate for an oil.  I later discovered that it wasn't evaporating, it was soaking into the rubber.  It also soaks into nitrile gloves without any apparent change to them other than being infused with the smell.  I used long nose pliers to pull a soaking part then wiped the pliers with the gloves and the oil vanishes.  After pulling another part I left the pliers sitting and they were still oily about a half hour later.  I left them for a few hours and they appeared to be dry, but thy still had the smell so there was some left.  This tells me that it's being absorbed by the rubber parts I've put it on and not just evaporating.

 

I have another part in a Zip lock sandwich bag.  I was afraid that it would 'melt' the bag so I hung it over the garage sink, but several days later the bag looks fine.  It's permeating, I can smell it from far away and the fluid level has dropped.

 

On day one I spilled a bit on a 'grippy mat', one of those soft rubber mats that looks like little balls linked together forming somewhat of a screen looking thing.  It appears to have done nothing to it.

 

Somehow the stuff seems to restore rubber without going too far.  Like it's programmed to only alter stuff to it's correct state and stop, so strange.

 

The tires on the R5 are ancient, gonna need more wintergreen oil.

[SwampNut]

9 hours ago, superhawk996 said:

Like it's programmed to only alter stuff to it's correct state and stop, so strange.

 

Long-forgotten chemistry memories ahead, I know this is partially correct and very incomplete...  Rubber hardens from losing molecules, but the remaining molecules still have an affinity for another molecule.  So the new oil is absorbed and bound to the rubber.  Because of its low molar mass (pretty sure) the wintergreen oil should transfer easily.  Once the bonds are made with either old oil or new oil, no more oil should bind to the rubber.  Given enough time, the new oil could replace some of the old oil in "good" rubber, but probably wouldn't continue to enter the rubber because there would be no attraction.

 

The bag may be permeable by the oil, without actually absorbing/binding the oil.  Meaning that it may flow through.  Like I've tried to keep acetone in LDPE bottles, and it just disappears.  But it has zero effect on the bottle, and the smell goes away completely.  At a molecular level, everything is just a sieve; the question is how tight is it and what attraction points do the molecules have to each other to stick.  You put beans in a colander and they stay, put rice in and it falls through but a lot sticks to it because there's also an attraction.

 

@RXX could tell me where I fucked his up and fill in the blanks, probably.

 

With a precise scale (IE grain scale) you can easily measure the acquisition of oil, or not, in any substance.

 

[superhawk996]

8 minutes ago, SwampNut said:

 

Long-forgotten chemistry memories ahead, I know this is partially correct and very incomplete...  Rubber hardens from losing molecules, but the remaining molecules still have an affinity for another molecule.  So the new oil is absorbed and bound to the rubber.  Because of its low molar mass (pretty sure) the wintergreen oil should transfer easily.  Once the bonds are made with either old oil or new oil, no more oil should bind to the rubber.  Given enough time, the new oil could replace some of the old oil in "good" rubber, but probably wouldn't continue to enter the rubber because there would be no attraction.

 

The bag may be permeable by the oil, without actually absorbing/binding the oil.  Meaning that it may flow through.  Like I've tried to keep acetone in LDPE bottles, and it just disappears.  But it has zero effect on the bottle, and the smell goes away completely.  At a molecular level, everything is just a sieve; the question is how tight is it and what attraction points do the molecules have to each other to stick.  You put beans in a colander and they stay, put rice in and it falls through but a lot sticks to it because there's also an attraction.

 

@RXX could tell me where I fucked his up and fill in the blanks, probably.

 

With a precise scale (IE grain scale) you can easily measure the acquisition of oil, or not, in any substance.

 

That makes sense, thanks.

 

Everyone dilutes the oil with alcohol, or other stuff, I assumed it was because of the high cost of the oil and needing enough to submerge the parts.  One person said that the alcohol carries the oil into the rubber, then it evaporates, implying that the alcohol is needed.  Do you think the alcohol is needed, helping, or hindering the process?  I couldn't smell any alcohol on the parts, but the strong wintergreen smell might have been masking it.

 

I wonder what other oils could be used, especially if there's something cheaper.  Bonus if it doesn't smell so strong.

[SwampNut]

Alcohol is the most universal of solvents and a great carrier for so many things.  I wouldn't doubt that it helps, but not sure it's totally necessary.  Also just like adding water to whisky, it may break some molecular bonds to increase how it reacts to the rubber.  Bottom line-dunno.  

 

 

Perplexity AI explains it ok, not great:

 

The search results do not provide a direct explanation of how methyl salicylate binds to nitrile butadiene rubber (NBR). However, we can infer from the general principles of chemistry and the nature of the materials involved how such binding might occur.Methyl salicylate is an organic compound with a structure that includes both a benzene ring and an ester group. Nitrile butadiene rubber is a synthetic rubber copolymer of acrylonitrile and butadiene. The interaction between methyl salicylate and NBR is likely to be a physical process rather than a chemical reaction.The binding could be due to the following factors:

1. Solubility and Swelling: Methyl salicylate may act as a solvent for the NBR, causing the rubber to swell as the molecules of methyl salicylate intercalate between the polymer chains of the rubber. This can temporarily improve the flexibility and other mechanical properties of the rubber
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2. Secondary Bonding: There could be secondary bonding interactions such as van der Waals forces or dipole-dipole interactions between the polar groups in methyl salicylate and the polar nitrile groups in the NBR
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3. Compatibility: The chemical compatibility charts and resistance guides for various rubber materials, including NBR, suggest that certain chemicals can have little to no effect on the rubber, while others can cause degradation or swelling
   1
   3
   4
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   . Although these charts do not specifically mention methyl salicylate, they indicate that the compatibility of a chemical with NBR depends on the chemical structure and the resistance of the rubber to that structure.

In summary, while the exact mechanism of binding is not detailed in the search results, it is likely that methyl salicylate interacts with NBR through a combination of solubility, swelling, and secondary bonding forces. This interaction can temporarily modify the properties of the rubber, which may be beneficial in certain applications.

[SwampNut]

What is the relative volatility of Methyl salicylate compared to engine oil?

 

 

Methyl salicylate is a volatile compound, meaning it readily evaporates at room temperature[1][3][5][9][13]. Its volatility is one of the reasons it's used as a signaling molecule in plants[1][3][5][9][13]. However, the exact volatility of methyl salicylate in comparison to engine oil is not directly provided in the search results.

Engine oil volatility is typically measured using the Noack Volatility Test, which determines the evaporation loss of lubricants in high-temperature service[2][4][6][8][10][12][14]. The more volatile an oil is, the higher its Noack volatility number. Therefore, a low Noack rating indicates a high-quality oil[12]. The oil volatility is defined as the amount of oil desorbed from the column at a temperature of 371 °C, relative to the total oil desorbed or relative to a known quantity of some internal standard[4].

While the exact volatility of methyl salicylate is not provided, it's known to be a highly volatile compound[1][3][5][9][13]. However, without specific data or a direct comparison, it's challenging to definitively state the relative volatility of methyl salicylate compared to engine oil. It's likely that methyl salicylate is more volatile than engine oil given its use in applications that require a high degree of volatility, but this would need to be confirmed with specific experimental data.

Citations:
[1] https://en.wikipedia.org/wiki/Methyl_salicylate
[2] https://www.sciencedirect.com/science/article/pii/0040603189854747
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6863746/
[4] https://resources.perkinelmer.com/lab-solutions/resources/docs/app_the-tga-noack-test-for-the-assessment-of-engine-oil-volatility.pdf
[5] https://www.frontiersin.org/articles/10.3389/fnut.2022.1018534
[6] https://link.springer.com/article/10.1007/s41104-022-00102-y
[7] https://pubchem.ncbi.nlm.nih.gov/compound/Methyl-Salicylate
[8] https://www.savantgroup.com/media/SAE-961227-A-Laboratory-Method-for-Measuring-Bulk-Volatility-of-Engine-Oils-Comparative-Results-1996.pdf
[9] https://link.springer.com/article/10.1007/s00468-021-02191-y
[10] http://www.sciencedirect.com/science/article/pii/0040603189854747/pdf?md5=89a066237245834d6a1486600a08f9d9&pid=1-s2.0-0040603189854747-main.pdf
[11] https://health.ec.europa.eu/system/files/2022-08/sccs_o_255.pdf
[12] https://bobistheoilguy.com/forums/threads/lower-noack-better-oil.211659/
[13] https://www.sciencedirect.com/science/article/abs/pii/S095656632201048X
[14] https://www.savantgroup.com/media/Tribotest-Journal-June-2000-Analysis-of-Engine-Oil-and-Phos-Volatility.pdf
[15] https://apps.dtic.mil/sti/tr/pdf/ADA568827.pdf
[16] https://www.sae.org/publications/technical-papers/content/892159/

[SwampNut]

This might why NBR is resistant to oil, yet readily takes in the wintergreen oil.

 

What is the relative molar mass of Methyl salicylate compared to engine oil?

The molar mass of Methyl salicylate is 152.15 g/mol

1

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.Engine oil, on the other hand, is a complex mixture of various hydrocarbons and additives, and its molar mass can vary significantly depending on its specific composition. However, it's generally much higher than that of Methyl salicylate. For instance, the average molecular weight of Palm oil, a type of vegetable oil often used in engine oil formulations, varies from 810 to 855 grams per mole

6

.Therefore, the relative molar weight of Methyl salicylate is significantly less than that of engine oil.

 

[superhawk996]

I started reading about plasticizers.  I don't know if the plasticizers used in manufacturing can be put back into the rubber, but it would seem ideal since we know they last a long time.  I may reach out to some suppliers to see if they can/will answer that.

 

Several different plant based oils are apparently being used, or at least being studied, to replace petroleum and mineral based plasticizers.  I don't know if any of those can be effectively absorbed, but if they can it opens options.  Nowhere did I see wintergreen oil being used or studied, maybe because of the volatility.  What makes it great for putting into old rubber probably makes it bad for manufacturing/longevity.

[SwampNut]

Let's ask....

 

https://www.perplexity.ai/search/What-plasticizers-are-l24kRVxARAOSZNmmq8i9Uw?s=c#e7c3ccf5-0798-4e62-b532-b20021be7be7

 

[superhawk996]

Castor oil is one of the natural oils being talked about for manufacturing, should be perfect for the old two smoker's rubber parts.

[XXitanium]

15 hours ago, XXitanium said:

Good thing you don't live in California!

 

I'm looking for mySAFETY DATA SHEET - Fisher Scientific https://www.fishersci.com/store/msds?partNumber=AA43301&productDescription=keyword&vendorId=VN00024248&countryCode=US&language=en

 

...oh, shit,

 

MSDS maybe my stainless drinking cup aint so bad?

 

https://people.com/nanoplastics-discovered-bottled-water-8424730

 

 

 

[SwampNut]

1 hour ago, XXitanium said:

...oh, shit,

 

MSDS maybe my stainless drinking cup aint so bad?

 

https://people.com/nanoplastics-discovered-bottled-water-8424730

 

 

 

 

It is also, most likely.  Unless it's good 316, it's leaching a bunch of metals into your drinks.  Just watched a video cast about that and aluminum cookware.

 

We have polluted nearly 100% of the planet with nanoplastics, you can't avoid that either, like radiation.

 

"Climate and environment are fine, just ignore them!"

 

[IcePrick]

3 hours ago, SwampNut said:

 

It is also, most likely.  Unless it's good 316, it's leaching a bunch of metals into your drinks.  Just watched a video cast about that and aluminum cookware.

 

We have polluted nearly 100% of the planet with nanoplastics, you can't avoid that either, like radiation.

 

"Climate and environment are fine, just ignore them!"

 

 

Was working with a friend in his new shop yesterday, we were surprised that the welding he was doing was leaving little smoke in the enclosed space.  I mentioned that we were probably filtering it out through our lungs.  

 

Those little plastic nanoparticles will be broken down in our digestive systems.  It's a circle; the planet will be fine.

[tomek]

17 hours ago, SwampNut said:

 

 Just watched a video cast about that and aluminum cookware.

 

 

 

On YouTube?

[jon haney]

On 1/10/2024 at 2:30 PM, SwampNut said:

Hmm, would the ingestion hazard on that be swallowing or Keistering?

 

Yes.

[superhawk996]

I soaked a valve cover/PCV grommet from the Jeep, 1998 and probably original.  It was super hard, now seems about the right softness, but it swelled up quite a bit.  It seems to have happened in the last few days, it's been soaking for over a week.  It had softened without obvious swelling a few days ago, then today I noticed it was enlarged.  It doesn't seem obviously softer than it was several days ago and it doesn't look obviously distorted, just bigger.

 

 

 

[XXitanium]

Nobody can answer my question. Do you have an extra one of those later on that you could soften up and see how long it stays? Pliable? Apparently it's a big mystery.

[IcePrick]

Hmmm.  Gate gaskets for the Excursion are old, and unobtainable.

[superhawk996]

11 hours ago, XXitanium said:

Nobody can answer my question. Do you have an extra one of those later on that you could soften up and see how long it stays? Pliable? Apparently it's a big mystery.

If the grommet shrinks back to normal size it's getting installed.  If it won't, then I'll just hang onto it to see what it does.

[superhawk996]

11 hours ago, IcePrick said:

Hmmm.  Gate gaskets for the Excursion are old, and unobtainable.

If the issue is just that they've flattened-I bought silicone tubing and stuffed the hollow part of all my door/gate seals on the Ex.  It stopped all the rattles and noticeable air leaks.  I don't remember which size I used on the gate/barn doors, but I can check.

[IcePrick]

10 minutes ago, superhawk996 said:

If the issue is just that they've flattened-I bought silicone tubing and stuffed the hollow part of all my door/gate seals on the Ex.  It stopped all the rattles and noticeable air leaks.  I don't remember which size I used on the gate/barn doors, but I can check.

 

I did that with the door seals a couple years ago, and wasn't satisfied so I just bought new seals.  IIRC, they were too firm with the recommended size of hose installed.

 

If you had good results, yeah, I'd love to replicate them.  Going down the hill to PHX is (ob)noxious, low RPM coasting downhill doesn't get the exhaust gasses propelled outside of the vacuum envelope of the gate area, and some enters the cabin.   Opening a window while descending into Phoenix is generally regarded as poor form in the air conditioning conservation world.

[SwampNut]

With stinky vehicles in the past I've found that just a few inches of exhaust extension can make a huge difference.  I've also used generic foam seals on some vehicles, there are a LOT of shapes out there.  I can't remember what search I've done to find a page full of shapes to pick from.

 

https://www.google.com/search?q=epdm+door+seal&client=safari&sca_esv=598813290&rls=en&sxsrf=ACQVn09pzTybRL-2S_dV0z80i68kZ7CGtw%3A1705418775252&ei=F6CmZcP6Dt7AkPIPrsOk4A4&ved=0ahUKEwiD4qqCnOKDAxVeIEQIHa4hCewQ4dUDCA8&uact=5&oq=epdm+door+seal&gs_lp=Egxnd3Mtd2l6LXNlcnAiDmVwZG0gZG9vciBzZWFsMgsQABiABBiKBRiRAjIGEAAYFhgeMggQABgWGB4YDzIIEAAYFhgeGA8yBhAAGBYYHjIGEAAYFhgeMggQABgWGB4YDzIGEAAYFhgeMggQABgWGB4YDzILEAAYgAQYigUYhgNImx1QkBBY0xtwAngBkAEAmAF_oAH-B6oBAzIuN7gBA8gBAPgBAcICChAAGEcY1gQYsAPCAg0QABiABBiKBRhDGLADwgIFEAAYgATiAwQYACBBiAYBkAYK&sclient=gws-wiz-serp

 

[superhawk996]

56 minutes ago, IcePrick said:

I did that with the door seals a couple years ago, and wasn't satisfied so I just bought new seals.  IIRC, they were too firm with the recommended size of hose installed.

I seem to recall my doors being more firm than I'd like, but they softened after a while...or maybe I changed the hose size and don't remember it.  My barn doors are more firm than I'd like, the hatch seems fine.  I'll measure the hose I used when the ice caps melt.

 

Opening a front window will create a vacuum and likely worsen the exhaust issue.  Rear windows seem to create pressure, but possibly also a vacuum, and they'll create a pulsing if opened too far.  If yours has the vent function on the quarter panel glass maybe that would suck the exhaust out before reaching you.  Having the A/C on 'fresh air' should create cabin pressure and help keep exhaust out, but it also robs some very needed efficiency from the A/C.

 

https://shop.errecom.com/en/product/cool-shot-ultra/  This stuff helped my A/C.  There was a writeup in the late model 7.3 forum on Fordtrucks, I reported my findings with vent temps.  I don't remember the numbers, but it made a noticeable improvement.  I don't use my A/C much, but it's been in a couple years with no noticeable problems.

 

Semi-related: I had a few occasions where the climate control wouldn't power up, the screen was black, none of the buttons did anything.  I discovered 'the trick', turn the key off, cycle the headlight switch through on and auto and back off, then turn the key back on.  I don't know that it has to be cycled through all the positions, but it's what I read so it's what I did, and the problem hasn't reoccurred to retest.