Am looking for a clear and transparent thin plastic sheet 2

[frazelle09]

which will resist UV rays. We are building a parabolic solar hot water heater and for the parabolic collector we are trying to build a sandwich composed of 3 mm PVC on the bottom, a sheet of reflective Mylar .002 in. (i think it is) for the second layer and some sort of clear, transparent, UV resistant plastic for the top layer. We had purchased a sheet of 1/8" (or maybe it was 1/16") plastic which we were told was UV resistant and had used it for some six months when we suffered a catastrophic event with winds gusts of up to 67 Km/hr which essentially blew off the top two layers. The strange thing is that the top, clear sheet cracked into many pieces, leading us to believe that it was not UV resistant... (plus the fact that when we examined the pieces we found them to be slightly discolored).

Is there some sort of thin, clear plastic sheeting which is UV resistant? We're hoping for UV resistance of many years since these things are going to out in the sun full-time.

Have a wonderful evening!

 

[Pud]

Acrylic (PMMA sheet. It's mostly transparent to UV. Automotive rear light clusters are made from it.

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[frazelle09]

Thank you very much, Pud, for replying! i'll have to check this one out. As i was searching on the Net i was coming to the conclusion that a polycarbonate of some sort would be the way to go...

Again, thanks for taking the time to help and have a super morning!

"The earth is one country and mankind its citizens."
Bahá'u'lláh

 

[Demon3]

The UV stability of a given plastic type is as much about the additives in it as the plastic itself. So, you need to get the right plastic e.g. PMMA or SAN and then make sure the manufacturer sells you a grade specifically formulated for outdoor use. As an example, adding 0.1-0.3% of a UV stabilizer can make the difference between a 6 month life and a 10 year lifespan.

Chris DeArmitt PhD
President - Phantom Plastics LLC

Consulting, ideas and training on plastic materials

http://www.phantomplastics.com

 

[frazelle09]

Demon3, thanks for replying as well. That's good info, too.

Here's a link to the Appropedia site we're using...

http://www.appropedia.org/Parabolic_Solar_Hot_Water_Heater

Maybe i can find a place in San Diego, which is about 1.5 hours West of us, that can supply this type of sheet.

Have a great morning!

"The earth is one country and mankind its citizens."
Bahá'u'lláh

 

[berkshire]

You could also look at Du- Pont Tedlar and its cousins,
B.E.

You are judged not by what you know, but by what you can do.

 

[frazelle09]

berkshire! Thank you very much for your contribution as well. It's really neat to see so many ideas being suggested! We'll have to add it to our list to check out.

Thank you very much again and have a wonderful evening!

"The earth is one country and mankind its citizens."
Bahá'u'lláh