OK, but what do they mean in practical sense? If HDPE has a value of 2900 for O2, it passes 2900 cm^2/m^2.... Does that mean death to developers or is that an acceptable value? I have been storing mine in HDPE bottles and it is fine for all practical sense for over 6 months period. (so for my purpose, it's perfectly fine....)
For comparison purpose, do you have such data for Polypropylene which I did notice some color change.
For our purposes what is important is the ratio of any two values in the above table not their absolute values. Thus PET is approximately 30 times more efficient at blocking oxygen as is HDPE.
Polypropylene should be similar to polyethylene, maybe a bit better.
Last edited by Gerald C Koch; 03-20-2013 at 07:45 AM. Click to view previous post history.
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