Question about vinyl/rubber/plastic protectant composition

RPM WS6

New member
Great site you guys have here! I've recenly been reseaching vinyl/rubber/plastic protectants, and I stumbled across this great site. I've done a ton of searching here and read just about every thread on the differecnes between solvent based and water based protectants. But I have a question about terminology:



Once I learned that solvent based dressings (dimethyl silicone) are "bad" for vinyl/rubber/plastic with regular, long term exposure; and the water based ones (polydimethylsiloxane, or PDMS on this site) are "ok/good", I decided to look up the MSDS on my usual dressing of choice for these types of materials. Here is what I found:





Water: 60-80%



Dimethlypolysiloxane: 15-30%



Alkyloxypolyethylene oxyethanol: less than 2%




So my question is, what is the difference between Polydimethylsiloxane and Dimethlypolysiloxane? Is there a difference, or is it just two different ways of saying the same thing? Are they both water based silicone? And based on the MSDS info above, would you say that this dressing is safe for long term use on vinyl/rubber/plastic?



I've been using this dressing on all my interior and exterior trim and tires for MANY years now (since the mid-'90s) without an issue, and I really love the semi-gloss shine it gives, and how long it seems to last on the tires. But is it safe? I'm using it on my rarely-driven show car Camaro, so I'm looking for maximum longevity out of every surface on that car, and I don't want to do anything that will harm it long-term.



I may switch to 303 Aerospace for the trim (inside and out), but I like how my old product looks better on my tires.



So what do the experts here think? Thanks guys :)
 
Personally, 303 is a completely tried and true product that not only looks great on trim but is tested time and time again to work and last better than most other dressings. I would go with that for trim and maybe just use your old stuff for the tires since you like how it looks on that and if it hurts something... so what, just switch... no long term damage (due to frequency of replacement) that could be caused as if you were applying to trim.



However, keep in mind this is just opinion and I have no idea on the differences in what you've asked. Just wanted to share what I know works and is safe (and that I use on my camaro as well). For the interior, nothing beats Meguiar's Quick Interior Detailer on the plastics and Meguiar's Natural Shine on the "leather" parts, in terms of price, availability, and most of all looks.
 
Thanks for the reply :)



So you prefer Meguiar's Natural Shine over the 303 for interior? I really want to stick with just one product for all the plastic/vinyl trim inside and out, and I'm pretty well set on making the change to 303. But for the tires it just doesn't give the look I want (already tested that).
 
303 doesn't have the durability on tyres, a tyre gel is better.

Personally I'd rather polish exterior trims or use Renu it liner if I cant do that than use any dressings
 
The normally used term is polydimethylsiloxane (PDMS), aka silicone. There are differences in PDMS used in different applications, though. There are different molecular weight ranges for PDMS and different degrees of branching and crosslinking, all of which will give different physical properties. PDMS can range from an oil to a rubbery solid depending on these differences. The alkyloxypolyethylene oxyethanol is a surfactant, like a soap, that allows the PDMS to mix with water.
 
RPM WS6 said:
Thanks for the reply :)



So you prefer Meguiar's Natural Shine over the 303 for interior? I really want to stick with just one product for all the plastic/vinyl trim inside and out, and I'm pretty well set on making the change to 303. But for the tires it just doesn't give the look I want (already tested that).



Yes, I much prefer Natural Shine over 303 Protectant for the interior leather parts and QID for the plastics. As for the tires, I wouldn't use 303 on them, as has already been stated, due to the lack of real shine and longevity.



Getting things to look their best and last isn't about narrowing it down to one product that does "decent" on everything. It's about finding the right product for each area that does the best job.



However, if you really are dead set on one product for in and out, you could narrow it down to just Meguiar's QID for everything inside and 303 for the trim seals and exterior stuff.
 
wfedwar said:
The normally used term is polydimethylsiloxane (PDMS), aka silicone. There are differences in PDMS used in different applications, though. There are different molecular weight ranges for PDMS and different degrees of branching and crosslinking, all of which will give different physical properties. PDMS can range from an oil to a rubbery solid depending on these differences. The alkyloxypolyethylene oxyethanol is a surfactant, like a soap, that allows the PDMS to mix with water.



Thanks,



So, to your knowledge, is there a chemical difference between Polydimethylsiloxane and Dimethlypolysiloxane? Or is it just different terminology for the same molecular structure?
 
BuffMe said:
Yes, I much prefer Natural Shine over 303 Protectant for the interior leather parts and QID for the plastics. As for the tires, I wouldn't use 303 on them, as has already been stated, due to the lack of real shine and longevity.



Getting things to look their best and last isn't about narrowing it down to one product that does "decent" on everything. It's about finding the right product for each area that does the best job.



However, if you really are dead set on one product for in and out, you could narrow it down to just Meguiar's QID for everything inside and 303 for the trim seals and exterior stuff.



Why do you prefer the Megs QID for interior plastics? Due to appearance? Just curious, I was under the impression that 303 was "the best" (in terms of protection) for all plastics/vinyl/rubber.



What I dislike about QID is that it leaves no shine at all. The 303 seems to leave a nice, semi/low-gloss "glow", which I prefer. Also, does the QID offer any UV protection?
 
Speaking purely in terms of its purpose for longevity, 303 is "better" in terms of formulation for protection of seals and and other rubber/vinyl surfaces that may be exposed to harsh conditions. However, we're talking interior here, so the longevity and protection aspect is not *as* important. The interior isn't exactly exposed to weather conditions like the exterior of a car. So, I'd prefer something that looks and smells a bit better (Natural Shine smells great to me).



I prefer QID because it has great cleaning abilities and makes everything just look flat out fantastic. It leaves no oily or streaky residue like many others, which makes it great for the dull plastics in our interiors (but not our leather-type ones, which is why I use Natural Shine for those). Natural Shine looks awesome on the "leather" parts.



QID doesn't offer UV protection, but Natural Shine does, which is why I use Natural Shine on the dash and other leather type parts that get more exposure to the sun, and QID on the other plastic parts around the dash and console.
 
RPM WS6 said:
Thanks,



So, to your knowledge, is there a chemical difference between Polydimethylsiloxane and Dimethlypolysiloxane? Or is it just different terminology for the same molecular structure?



They are the same thing--but niether term describes a specific molecule. It is describing a "repeat structure" in a polymer, but there can be any number of repeat structures in each molecule, and they aren't necessarily in a line. Does this make sense? It's sortof like describing a train by describing one car, but the train can have any number of cars. It's actually more complicated than that because of branching, branch lengths, etc.
 
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