Myths... Dimethylsiloxane

[metroplex]

This post by DETAILKING caught my attention:




I agree to an extent. All silicone is not bad, it is the type of silicone that matters. When people say "silicones" are bad for paint, they are referring to dimethyl silicone oil. This is the cheap, greasy, oil, that shines like crazy and is in some detailing products. It is a fact that this type of oil on your paint can be very difficult to remove as it finds it way and leaches into cracks and voids. If it is not removed completely when repainting a panel, "fisheyes" can form in the paint. This is confirmed in an article out of Professional Carwashing & Detailing Magazine. Oct 2000 issue - Caring For Today`s Automobile Finishes. "....Detailers should polish with non-silicone, body-shape-safe products. Silicone causes fish eyes. Occasionally, vehicles are polished and then need paint repairs within a very short period of time. If silicone-based products were used and were not cleaned off properly, they can cause fish eyes in the paint finish...."



Dimethylsiloxane is used in Liquid Glass as the polymer protection component, same as Turtle Wax Finish 2001 and NuFinish.

It is also found in Meguiar`s #20, Gold Class, and if I recall correctly #26. It is a very common silicone oil used by many manufacturers for many different products (i.e. Permatex Dielectric Tune up Grease, Silicone spray lubricant, Damping oil for machinery, etc)

[imported_RIC]

Correction. I am not sure about the other products you listed but Liquid Glass contains PolyDimethylSiloxane. This is different than regular Dimethylsiloxane(dimethyl Silicone oil).

[metroplex]

I thought DETAILKING was referring to polydimethylsiloxane.



In any case, the products I mentioned contain polydimethlysiloxane.



I just noticed that on many MSDS sheets they either do this:

poly (dimethylsiloxane)

or "dimethysiloxane" (poly) but they all have the same CAS #.



The stuff in Liquid Glass is the same silicone oil used in Finish 2001 and NuFinish and Gold Class, etc...

[imported_RIC]

Detailking was not referring to PDMS.

[metroplex]

Ah that clears it up then. :)



I do not believe I`ve seen DMS used in many products...



PDMS is used in many products:

silicone spray

RTV

damping fluid

etc...

[buda]

If I might add to this discussion. There are two types of silicones used in today`s automotive dressings:





1. A water-based silicone emulsion and,



2. A solvent based silicone



There is nothing wrong with using a water-based emulsion, save the silicone will have a problem in body-shops but detailers are not body shops.



The culprit is the solvent based silicone. The base concentrate is mixed with something like mineral spirits or naptha to extend it and make it a dressing. However, this products is "murder" to rubber.



No supplier will tell you to use it on the interior because it is too slick and greasy.



So, use it on engines! But what about the rubber belts and hoses? It will breakdown an deteriorate the rubber. Also, solvents have a low flash point meaning that you could get a flash fire if the engine were hot.



Use it on tires!! A great tire shine. What are tires? Rubber! Plus, and this is a proven fact, when the solvent combines with the carbon black in tires it forms a liquid that when slung on the plastic body parts of a lighter color will irreparably stain the paint.



There is no place for solvent based dressings in the auto detail industry. Yet, the chemical companies still produce it. Why? For t the money, no integrity.



Regards

BUDA