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lawrenceSA
11-05-2014, 05:16 AM
As we all know there is a lot of misinformation and misunderstanding when it comes to the actual science behind what is happening when we detail cars.

As someone who never took chemistry at school and has a very limited knowledge of I often struggle to weed out the truth from the marketing hyperbole and general misinformation.

Having spent some time on AG it is quite obvious that a lot of you have a vast knowledge of the subject.... one that springs to mind is PiPUK but there are obviously others who's forum nicks I cannot recall right now.

I am really keen to learn as much as I can (within reason) about the chemistry so that I can make better choices when it comes to selecting products etc.

So I guess the question is, what are the chances of the more knowledgeable members 'teaching' us noobs about chemistry and if this is not an option, do you have any suggestions about where I should look as a source to obtain this info?

I get that it is impractical to expect to obtain the level of knowledge that the actual chemists who formulate the stuff have - it is their area of expertise and they have a lifetime of learning under their belts, and I get that as Mike Phillips often says, it is more about what the product does that what it says on the label or what is in the bottle, but I really want to try and improve my knowledge as best as I can.

Thanks in advance:xyxthumbs:

Dereksdtail
11-05-2014, 05:36 AM
^right on

Paul A.
11-05-2014, 10:42 AM
I would love to hear more of the science side too. I can also understand how comprehensive this subject is for our more knowledgeable chemistry or engineering experts to "just start explaining" stuff. Not that easy for them to do so we can grasp the concepts so...

Here's my suggestion. Maybe someone who understands the composition of vehicle paint systems could impart a little subject matter expertise in that area. What are the different paint compounds, how are they applied and what is each layer comprised of? Yes, i know...we all have a basic knowledge of car paint...we certainly have a bunch of experience rubbing, cutting, buffing etc on it but what is the chemical makeup and what contributes to some paints being soft and some hard? Something more scientific as a basis for then going into the chemistry of abrasive chemical formulations, non abrasive chemical "cleaners"etc. Ya know, something beyond primer, basecoat, clearcoat and relative thickness of each...more like the chemical properties of what's used before then going into the chemistry of the compounds, polishes etc that then are used on that paint compound.

More like "Chapter 1 - Paint" and provided as a basis to then go into Chapter 2 - The Chemistry Behind Why Polish Works.

Just a thought but i have loved the more scientific discussions from our friends here who know sooooo much more of the science side of it than me. And my suggestion offers maybe a logical starting point to build on...The Science And Chemistry Of Paint.

Audios S6
11-05-2014, 10:59 AM
A very rudimentary primer of pH and it's principal effect on cleaning:

The pH scale is logarithmic, so each number represents a 10x change in H or OH.

Low pH represents free H molecules (acidic). High pH represents free OH molecules (basic/alkaline). 7 is neutral with H & OH present is equal quantities; it does not necessarily represent an absence of either, although frequently we would expect the free H & OH to react with each other to form water and a secondary compound as below

sodium hydroxide + hydrochloric acid:
NaOH + HCl ----> NaCl (table salt) + H2O (water)

Nonorganic/Mineral compounds (iron, salt and similar) tend to be best cleaned with acids. Organic compounds (soils, grease and similar) tend to best be cleaned with alkalines.

pH is generally not relevant to solvents (as we use them in detailing) as free H/OH do not exist in the same manner. Solvent is a broad term that can characterize many things - water being a solvent for table salt. Solvents as we think of them in detailing are most often petroleum distillates aimed at removing other petroleum based products (tar for example). The concept being that like dissolves like.

Another term you may see would be a chelating agent. This is a compound that binds to other compounds in solution preventing them from re-suspending or reacting in the solution. One example is mercaptoacetates that bind iron as you would find in many color changing wheel cleaner.

I'll leave the details of reactions related to sealants to others, but essentially you have a large volume of siloxane molecules and a portion of reactive siloxanes that in the presence of oxygen and moisture will react with the normal siloxanes binding them together chemically.


I am far from a chemist so if I have misrepresented something, please do correct me.

Paul A.
11-05-2014, 11:49 AM
Wow! Awesome Audios, thank you friend! Yes, pH is often discussed here and that explanation helps. I never knew it was a 10X scale.

And a nice explanation of why Iron X transforms like it does!

RobRabbit2.5
11-05-2014, 12:14 PM
As we all know there is a lot of misinformation and misunderstanding when it comes to the actual science behind what is happening when we detail cars.

As someone who never took chemistry at school and has a very limited knowledge of I often struggle to weed out the truth from the marketing hyperbole and general misinformation.

Having spent some time on AG it is quite obvious that a lot of you have a vast knowledge of the subject.... one that springs to mind is PiPUK but there are obviously others who's forum nicks I cannot recall right now.

I am really keen to learn as much as I can (within reason) about the chemistry so that I can make better choices when it comes to selecting products etc.

So I guess the question is, what are the chances of the more knowledgeable members 'teaching' us noobs about chemistry and if this is not an option, do you have any suggestions about where I should look as a source to obtain this info?

I get that it is impractical to expect to obtain the level of knowledge that the actual chemists who formulate the stuff have - it is their area of expertise and they have a lifetime of learning under their belts, and I get that as Mike Phillips often says, it is more about what the product does that what it says on the label or what is in the bottle, but I really want to try and improve my knowledge as best as I can.

Thanks in advance:xyxthumbs:

I think that this is a very interesting post and could even lead to another forum heading where individuals could post information regarding chemicals and paint systems from reputable sources of information. It's all about really putting the geek in Autogeek.

I'm not sure what the title of the sub-forum would be but i'm sure the creative director over at AG could come up with a savvy one after he finishes his steps over at SEMA.

After reading this post i did some research online and found some interesting information. One was a book published a long time ago 1998 about car paint systems that is targeted at autogeeks. I have the link and would like to provide it however it does have information very similar to the stuff provided by Mr. Phillips in his books and I don't want to break the forum rules. If i get the go-ahead i will gladly post it. Looks like some good info.

I also did some research into scientific journals to see what information is available for free. The information available online is limited. The studies are available for purchase but cannot be read yet free of charge. They are released after a period of time (seems to be about 20 years) which makes the information obtainable without purchase largely outdated due to an ever-changing progressively innovative automotive industry.

I did find out a few things from the titles and short descriptions.

1. There are a bevy of tests used to determine the quality of automotive paints, and products that are used to coat and protect them. These are advanced pieces of equipment that look at microscopic levels, infrared radiation, x-ray, etc... The language of the journals requires college level understanding of chemistry, physics, etc at minimum. I will post the link for this if it's not against forum rules.

2. There is a National Automotive Paint File that is under repository by the FBI in the U.S that has categorized over 40,000 different automotive paints since 1930. This information is used during forensic analysis to help solve crimes. There is something similar in canada and other countries as well. Apparently the info for the paints is detailed and vast. I have yet to look into it but it may be public record and worth investigation.

3. There is cutting-edge science going on right now into creating coatings that self-heal using thermodynamics. The coatings are similar to the coating of a bean, and also some research into the shells of crabs and shrimps and how they can heal damage from scratches environmental factors. It's very exciting, but also has worrisome implications if paint can heal itself (correction absolete...) Seems like carnuaba wax set a high bar...

RobRabbit2.5
11-05-2014, 12:20 PM
Wow while i was literally typing the giant block of text above someone posted a link to a product released at sema from CarPro that heals when it is heated.

This is cutting edge stuff. I'm now fully into CarPro.

Link: http://www.autogeekonline.net/forum/auto-detailing-101/86446-carpro-immortal-self-healing-coating.html

lawrenceSA
11-06-2014, 02:31 AM
This is awesome

Please keep the info coming.

I also agree that maybe we should break it up into bite sized chunks and put some structure to it.

So for example some suggested 'topics' could be.

Wheel cleaners - Acidic vs alkaline and the effects of each. how to neutralize them etc.

Paint - what is it made of, pros/cons of each

LSP's - what types of bonds are formed with each type *wax/sealant/coating*.

Washing - shampoo types, surfactants etc

Basic chemistry principles -

Etc
Etc