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Old 06-20-06, 08:49   #30 (permalink)
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Quote:
Originally Posted by Grouse
... I can see how you could claim paint being viscous, but i have no proof or knowledge to it being that way.
Current paints aren't. It's claimed that these new self healing paints are.

Nissan's coatings are produced by Nippon Paint and while they've been happy to tell us how wonderful it will be they haven't been too clear on how it works.

Bayer in Germany is also working on self-healing coatings. By formulating the finish with a low glass transition temperature (the temperature at which a solid polymer will start to behave like glass, a viscous non-crystalline amorphous solid) the scratches will tend to flow out when warm.

Of course it's a balancing act of making the coating flow when you want it to but not when you don't.

Then there are other issues to contend with. Bayer says the self-healing works for scratches caused by plastic deformation of the surface, when the molecules in the matrix are displaced but bonds aren't broken. Apparently it doesn't work for scratches caused by brittle fracture, breaking of the intermolecular bonds. So the coating has to both flow and yet resist fracture under normal use. That's got to be tricky to do.


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