The square polyethylene coin tubes by Colella are very handy for storage where you don't need to see your chips individually or keep notations regarding each chip nearby (like writing on a cardboard holder). The square ones also stack nicely in a safe deposit box and won't roll around.

You don't need to worry about plastics damaging your chips at all in my opinion, but certainly not polyethylene.

The link below is to a dealer's site where you can see a pic of what I'm talking about.