Re: ATM UV protection for epoxy?

[Bruce Swayze <swayze@europa.com>]

At 12:47 PM 7/29/97 -0500, you wrote:
>I would like to make the surface of epoxy composites resistant to
>sunlight.  Sure, I could cover the surface with some paint which is
>resistant to sunlight, but that would just add weight without adding
>strength.
>
>When I mix epoxy with milled glass fibers, perhaps also some glass
>microballoons, and some white pigment (dry ground TiO2, titanium oxide),
>the surface of the cured composite rapidly acquires a yellowish tinge
>when exposed to sunlight -- presumably because the ultraviolet rays in
>the sunlight attack the epoxy near the surface.  I suspect that
>continued exposure to sunlight over the years would seriously weaken the
>top surface of the epoxy.
>
>So, I've got some questions.  
>
>1.  Is there something which I can add to the top layer of epoxy which
>will keep it from discoloring in sunlight?  (without screwing up the
>properties of the epoxy)
<snip>

Gerry,
Check out the web page for West Systems epoxy, and you may find some
answers.   They also make reference to a resource of users similar to this
atm list.  They can be found at:
http://www.concentric.net/~westsys/index.shtml    Good luck!  

Bruce Swayze