>> I knew epoxies were no good in moisture.

> Epoxies do relatively well in moisture unlike polyesters. 
> They don't
> do too good with UV though, but then very few things can 
> stand UV.

As I noted, "silicon rubber" is inherently superior to 
almost anything else because the Si-Si bonds are higher 
energy. The physically longer bonds (if you allow that the 
metaphor of length has meaning 'down there') also leads to a 
generally softer end product all other things being equal, 
although you can still get a range.

It's not a coincidence that the window 'putty' that you see 
still sort of hanging in there after 20 years is silicon 
based.

If you can get some UV inhibitor in the mix, so much the 
better.

Some UV inhibitors work by absorbing UV and then fluorescing 
and releasing light of longer wavelength. So the energy is 
not absorbed, just transformed. When trialling a silicone 
coating with a solar panel I found that panel output rose 
slightly coated wrt uncoated. There are a number of possible 
reasons for this but eradiation of UV into panel usable 
light may help a little.


        Russell


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