8 Apr
2016
8 Apr
'16
12:43 p.m.
On 04/08/2016 12:11 PM, Tom Gardner wrote:
Sorry, to a EE they are all epoxies, but:
Gorilla glue is an epoxy? News to me.
Polyurethane is far from stable over the long term and exhibits
hygroscopic properties:
For example, vide:
http://www.ptonline.com/knowledgecenter/Plastics-Drying/Resin-Types/Hygrosc…
...and many others.
Floppy and tape binder also is somewhat of a witches' brew as it usually
includes a fatty acid or some other substance for lubrication.
As far as "stability", that's subjective. Most plastics will eventually
degrade; some are worse than others. There's a big problem in the
museum archiving business that not much, other than freezing seems to
retard eventual decomposition of plastics.
--Chuck