What's wrong with silicone in protectants?

[adreed24]

I've been doing some research on the phone and Internet, about car vinyl/rubber protectants that you can use on the dashboard, door panels, etc.

Some people, including the "303 Aerospace" people, say that silicone is bad for vinyl, rubber, and other interior parts.

On the other hand, the "Meguiar's" people say that there is nothing wrong with silicone; they say that it is inert and does no harm.

Other people I've spoken with, say the only reason silicone is used in so many car protectant products, is because it is so cheap and makes things look shiny and new.

I've used "Armor All", "Black Magic", "Vinylex", "Finish 2001" (it's called "F21" now, I think) and I haven't noticed any problems caused by the products themselves, except some are greasier than others, or don't last as long.

Since so many car products contain silicone, how can it be bad for cars?

Is silicone really good for protecting vinyl and rubber?

Are there different types of silicone, good and bad?

Companies can be confusing sometimes.

Any comments anyone?

Thanks in advance!

[ May 07, 2005, 01:43 AM: Message edited by: adreed24 ]

 

[tuong]

I dont have an answer to your question. I do have a suggestion on the products you use, there been many posting here as well. Any oil base product u use on your vinyl and rubber will crack. I you would use MOhters Water base vinyl and rubber base, it would prevent this. Again I odnt know your answer to silicon

 

[Colt]

Ive heard silicone magnifies the sun which makes vinyl dry out faster.
Myth?

 

[hone eagle]

I was warned by my boat re-finisher that silicones if not completely removed we would get fish eyes in the paint.They are VERY difficult to eleminate and they are his personal nitemare.

 

[ruking77]

Me thinks it has to do more with other ingredients: problem is, it is guilt by brand association being as how most of us dont have a CSI to analyse what the offending compound is!.

For example, I have put "silicon" dielectric grease on door seals on a Corvette Z06. The seals are as "moist" and absolutely "TACKY" as when I put it on (5 years ago). To BOOT, this silicon dielectric grease is a left over from my Air Force missle days (discarded due to shelf life being exceeded)

So it was considered trash and in fact I fished it from the TRASH, (in case the statue of limitations has not run out!!)

in 1974-1976, which if you factor in 2001 that is 25 years. If you factor in 2005 (still good) then we are talking 31 year old PRODUCT.

Silicon has been shown to make MAF and its circuitry fail prematurely. So personally I'd be VERY care to NOT apply it where it can be ingested by the vehicle's air intake system.

 

[BenDarDunDat]

quote:

---

Originally posted by ruking77:
Me thinks it has to do more with other ingredients: problem is, it is guilt by brand association being as how most of us dont have a CSI to analyse what the offending compound is!.

For example, I have put "silicon" dielectric grease on door seals on a Corvette Z06. The seals are as "moist" and absolutely "TACKY" as when I put it on (5 years ago). To BOOT, this silicon dielectric grease is a left over from my Air Force missle days (discarded due to shelf life being exceeded)

So it was considered trash and in fact I fished it from the TRASH, (in case the statue of limitations has not run out!!)

in 1974-1976, which if you factor in 2001 that is 25 years. If you factor in 2005 (still good) then we are talking 31 year old PRODUCT.

Silicon has been shown to make MAF and its circuitry fail prematurely. So personally I'd be VERY care to NOT apply it where it can be ingested by the vehicle's air intake system.

---

Uhh, it IS "silicone", you know.

 

[XS650]

quote:

---

Originally posted by ruking77:
To BOOT, this silicon dielectric grease is a left over from my Air Force missle days (discarded due to shelf life being exceeded)

So it was considered trash and in fact I fished it from the TRASH, (in case the statue of limitations has not run out!!)

in 1974-1976, which if you factor in 2001 that is 25 years. If you factor in 2005 (still good) then we are talking 31 year old PRODUCT.

---

Are they still using good 'ol DC4 (Dow Corning 4) silicone coupound like they were in the 1960s?. It was good stuff. I bet is has a longer shelf life than Twinkies.

 

[bretfraz]

This is a very complex topic that has no simple answers.

There are over 30,000 formulations of "silicone". Obviously not all of them are bad for automotive plastics, rubber, vinyl, etc. But to clearly determine safe or unsafe silicone would take an advanced degree in polymer chemistry and thousands of $$ of research as you would have to literally test every product just to get an idea of what's in it.

Regarding automotive protectants and dressings, there are two basid types of silicone used - dimethal silicone oil (DMS) and polydimethalsiloxane (PDMS). DMS is very inexpensive (IIRC you can buy a barrel of DMS for under $100) and it's typically found in cheap, oily dressing products. If the dressing you're looking at is clear, looks and feels like baby oil, and is very shiny, it probably has DMS in it. The problem with DMS is it's migratory. it enters the pores of the plastic and rubber, leeching out the chemicals designed to keep the item flexible and protected, and accelerates oxidation, drying and fading.

PDMS is mainly used in water based dressings. It's easy to tell which product has PDMS in it - if the product is milky white and feels watery and just a little slippery, it's likely PDMS based. PDMS is the "safe" silicone protectant and some formulations actually offer UV protection and repellency from dust and water. The only negatives about PDMS dressings are their lack of durability and their higher price compared to oil-based DMS dressings.

So for car enthusiasts, I recommend buying a protectant that is water based and applying as needed. Over time you will use more PDMS dressing but it should provide much better long term protection.

This will always be a confusing topic because the chemistry is so complex, the education of consumers is difficult, and the profits from these products are very high. There is no motivation for any car care products mfr to tell you the chemical details of their products. So I think the best thing to do is use products you know are safe based on your research and stick with them. Personally, I'd never buy an oil-based dressing unless it was something new I wanted to test just once.

There are many excellent water-based dressings on the market. Try a few and find one you like.

 

[Russell]

It is my understanding the Armor-All Orignal is now water based. Many years ago it was supposed to be solvent based. Not proven