That's false. Silicone is widely specified to lubricate rubber o-rings, plastic parts, rubber door mouldings, etc.
Permatex is one of the most trusted names in chemical tools in the automotive industry:
https://www.permatex.com/products/l...lubricants/permatex-silicone-spray-lubricant/
Actually, you are out to lunch. First, GASKETS AND SEALS are NOT Door seals.... Are they? So your argument fails right there. Secondly, you have no clue what is in various silicone sprays. Or what type of rubber the seals are, and what plastic trims lie underneath. Hexane, Naptha, solvent conducers, are bad for plastics, and often where you have silicone there is some plastic as well.. these attack the polymer links, leaving you with a weakened material after. A top North American company's silicone I was about to try, on testing it wiped on my paper towel black rubber marks on contact, and am glad I never continued. The spec sheet said "Safe for rubbers" but in practice, it was not. why? SOLVENTS. So unless you know chemistry, you cannot generalize SILICONE IS SAFE. Not all silicone sprays are equal, and most are bad...
You also make another bad mistake: HEEDING ACTUAL EXPERTISE ADVICE. Detailers that claimed poor silicone effect on DOOR SEALS ad CAR TRIMS and PAINT types have worked on 1990s Nissans Gt all the way to Bugattis. They know their stuff. Perhaps instead you should read:
Polydimethylsiloxane (PDS) is a basically inert, water based, amino functional polymer resin that doesn't migrate (dry out) the plasticizers from materials, has less UV radiation absorption and dust attraction properties. Chemists use water-in-oil emulsions, to reduce emulsion particle size, to stabilize emulsions, and to improve spreading and coverage of wax products. Most modern silicone formulas are water soluble (no petroleum), and are completely inert.The best way to describe most forms of silicone is to think of it as a man-made wax ester. Silicone is created by the reaction generated when you combine fatty acids with Polydimethylsiloxane
The Bad: Dimethyl is derived from Aromatic hydrocarbon (petroleum) distillates, and is usually formulated with a solvent, hexane and petroleum oils, which are environmentally unsound and give a slick, oily finish, which attracts dust and dirt and amplifies sunlight causing vinyl and most plastics to dry out and crack, this type of silicone also causes ‘sling’, which means the product will land on body panels causing a black stain. It also causes rubber compounds along with sun iteration to remove the micro-wax in tyres as well as its carbon black (it's what makes tyres the colour they are)
And The Ugly: Silicone is an active ingredient in sun UV amplification. As a low quality silicone dressing evaporates away, the silicone oil is left behind, the sun then amplifies these residues, and the drying process is accelerated. This causes rubber, EDPM, vinyl and plastics to dry out, which turns them grey or brown, losing their flexibility and prematurely fail. Water-based dressings do not contain oils or petroleum distillates and provide a non- greasy, natural looking satin finish.
You also make another bad mistake: HEEDING ACTUAL EXPERTISE ADVICE. Detailers that claimed poor silicone effect on DOOR SEALS have worked on 1990s Nissans all the way to Bugattis. They know their stuff. Perhaps instead. Source:
The good and the bad types of silicone.
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But here is the personal experience that you should pay attention to. After several summers of siliconing Japanese and German car rubbers (or whatever they are, not all are pure rubber)- REGULARLY- Noticed how by winter the darn things were HARD and squeaking, rattling and whistling. On my older cars, the seals started cracking and dried very fast... Asking around experts- and my city has 2- they replied exactly the same: SILICONE IS BAD ON DOOR SEALS.... You comparing gaskets with and UV exposed door seals is another argumentative issue.
Point is , I LEARNED MY LESSONS, I used Ph Neutral mild soap to gradually clean my cars, then went GUMMI. And, like magic, old rubber became soft, waterproof, hydrophobic and souple, nasty creaks disappeared, and I did not have to spend hundreds of $ per car replacing them... So instead of a monthly clean, once per year Gummi and no more problems..
So keep dishing bad advice and how oils or silicone are good for GASKETS, vs a completely different scope rubber...