Sintra (PVC) vs Styrene and UV Stability

[kfinnn]

This will sound like a dumb question from someone in the large format business for over 10 years, but which board, sintra (PVC) or styrene is UV stable? I'm hearing conflicting information from suppliers and production experts. I remember when I first started I was using Sintra for some outdoor displays. We live in a desert climate where summer temps reach 105 on a regular basis. I did an office sign using laminated adhesive vinyl on Sintra and it yellowed and cracked after being out for about 6 months, the last two during the summer. The print was fine, but the board practiacally disintegrated. When I asked our supplier about this they told me that Sintra was not UV stable and I should switch to styrene. I have used styrene ever since, as long as the piece wasn't over 24 x 36 as it gets too floppy any larger than that. I have not had any complaints from customers who got the styrene.

Recently I've started working at a new company and they believe that it's Sintra that is UV stable and styrene is not. I started researching this issue and almost universally I'm finding that the majority of opinions agree that Sintra is UV stable and styrene is not. Can someone please clear this up for me once and for all?

 

[miker]

I believe Celtec is the only brand of PVC that is rated for outdoor durability

 

[GVP]

I would think pretty much any plastic would be short term in a desert environment?

 

[FireSprint.com]

I want to open this back up again.

From what I have learned, styrene will yellow and crack after a few months or years depending on the environment. Sintra or PVC will last a bit longer and High Density Polyethylene or Better yet Polycarbonate (Lexan) will last the longest).

Not sure where standard acrylic sits in there.

Does that seem right to you guys? Chime in with references if you have some.

 

[dlndesign]

I think the one thing that isn't being discussed is thickness. In your examples how thick are these signs? I have made 3MM Sintra Signs in San Diego for almost 10 years, they hold up fine, and even during the hot summers. Styrene is rarely used because it is not ridged enough for outdoor signage, which they typically go in doors and into a frame or are clipped. Now if the scenario is that you have a sintra or styrene sign inside of a window that faces the sun all day, then your signs will disintegrate rapidly some not even lasting 3 months. Thicker pieces of styrene even hold up well as exterior signs as dimensional lettering, typically 6MM and above.


http://www.cmykthis.com

 

[synergy_jim]

styrene yellows with outdoor UV exposure. Most PVC's will outlast styrene outside by far.

 

[Gino]

Around here, not much in the way of styrene or sintra works, let alone the other brands. While these products are non biodegradable to some degree, they aren't truly outdoor products. Maybe they won't rot like wood or dent, but most plastics in our industry are for indoor use only. While we have four seasons here, all of them take their toll....... from frigid weather making them brittle to the hot sun warping them and making them wave like crazy. As for styrene yellowing, that's an old well known condition that happens to it, whether inside or outside and they don't have to be in a window having the sun hit them. The product starts yellowing naturally after about 6 months to a year according to what thickness you get.