Krytox

[mark b]

Anyone hear of this stuff? It's made by Dupont for preserving weatherstripping. Supposedly a totally new product, but it's not cheap. I saw it for $32 for 2 oz (yes, 2 oz not 20!)

At the price of new weatherstripping, if it works it's worth it. I know Armorall, Formula2000, whatever will not protect stuff for very long. I've never seen a non-garaged car go 10+ years without cracking.

 

[myclone]

I used Krytox ~7 yrs ago at work on rubber O rings that were subjected to extremely high heat (1.7-2kdeg F). I dont recall much about it other than it was in paste form and we coated the O rings that were used to seal furnaces used in making fiber opitic strands.

The thing I do remember is the stuff was like axle grease and hard as hell to get off your hands/clothes. It seemed to keep the O rings from breaking down/cracking in the high heat enviroment we used it in and it aslo helped the sealing ability as the furnaces were water cooled/nitrogen purged.

The only thing Id worry about is if the stuff will protect the weather stripping from the UV of the sun and getting the stuff on you when getting in or out of the car.

 

[ijames]

Krytox is a trademark of DuPont (I'm pretty sure) for a line of polyperfluorinated ethers, of the form CF3CF(CF3)CF2-0-(CF2(CF3)CF2-O)n-CF3, with maybe some (CF2CF2)m mixed in, that's been around for at least 20 years. Depending on the molecular weight they are anywhere from a thin oil to a thick grease. They are very heat stable and inert towards oxygen. They are used in the semiconductor industry in vacuum pumps to suck out all the really nasty chemicals used in etching silicon to make ICs, including hot oxygen gas. I've ordered two kilograms (2.2 lbs x 2) of vacuum pump oil for $1000/kg before at work (don't spill that bottle ). Fomblin is a similar polymer line from Montedison. I've never heard of them being used on weatherstripping but they are very UV and high temperature stable. None of the commonly available solvents (acetone, lacquer thinner, alcohol, varsol, soap and water, etc.) will dissolve the stuff, so rubbing it off is your only option if you get it on you. Oh, forgot, Krytox greases were one of the big advances that made winchester disk drives possible back in the 80's - a thin film on the surface of the disk lubricates the head and keeps it from crashing as it comes into contact with the surface.

 

[mark b]

As usual, stellar info Carl!

Is it possible this stuff was not commercially available before and now is being marketed for the commercial auto sector?

At $32 for 2oz it sounds like a black-market contender against smuggled freon

 

[ijames]

No, it's been available commercially since at least the early 80's, and I think the Fomblin's were available before then. They are used in lots of vacuum applications, as mechanical pump oils, diffusion pump oils, and lubricating greases. I think they use the grease on some space stuff, too. Maybe some one just recently decided to try it on automotive rubber and thinks it works and will sell? It sure won't wash off. Oh, I forgot to add that if you look at the formulas I posted, Krytox is basically perfluorinated polypropylene glycol and the Fomblins are either perfluorinated polyethylene glycols or block copolymers of perfluorinated polypropylene and polyethylene glycols (if anyone cares ). Way back when I once got a fellowship for a year because I was using Krytox's as samples in a new mass spectrometric technique I was involved in developing (laser desorption Fourier transform mass spectrometry) and a guy from IBM got all excited when he saw my data while visiting the department at an alumni get-together. He sat down with my boss and I and we showed him all that we were doing, and he didn't really say much but went back to San Jose and put a check in the mail. Wasn't until about three years later that they told us that they were using it in disk drives and hadn't been able to work out any way of analyzing them.

 

[ThikStik]

I use it in servicing anesthesia machines-as ijames points out, it is nonreactive to oxygen. RE; weatherstrips or any auto plastics. I use baby oil. Ive cracked too many parts using stupid Armorall and the like. The word is, they use alcohol as a base and it drys out the plastic. Ive heard of water based protectants but cant find them. POR advertises a protectant with more plastisizers in it. Ill try it one day. I can say this for sure-DONT put protectant on outside door swseeps that are old and dry at all. Armorall will crack them like an egg. And it cracked my Chev truck vent window rubber too. Im D#$% tired of bad products out there.