Rubber Bands

What is the problem with the new rubber bands like the ones I can buy at Staples? They seem to lose their elasticity in a month or so? They also
get brittle and break after a few months of use in a file drawer.
I have some old files that use rubber bands from years ago. They still have their elasticity and don't break until really stretched.
Were the old ones made from real rubber? Are the new ones made really cheaply in China?
Al
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Al:
Typically the problem is ozone attack or ozone aging. See: http://www.ucar.edu/learn/1_7_2_28t.htm and http://www.corrosionservices.com/rubber.php
For more, Google those terms as phrases. Most materials have environmental Achilles heels.
Pittsburgh Pete
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On Feb 5, 8:42 am, snipped-for-privacy@hotmail.com wrote:

If you want to keep them long the secrete is 1)Airtight 2)No light and 3) Cool (from http://www.therubberband.info/faq.php )
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snipped-for-privacy@hotmail.com wrote:

pointing out failure mode is fine and dandy, but it doesn't point to the better materials for this application. butyl rubber as used in bicycle tire inner tubes cuts into loops well and is a good deal more environmentally stable. better again are the silicone rubber bands sold in the hair-care section of the local pharmacy. and they come in pretty colors!
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