Shelf life of epoxy

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Pandora

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I have some SP Systems SP106 resin, must be over 6 years old now, how long does it keep for? I know the shelf life quoted is usually low, but is that just because the catalyst does not last long, and they are normally sold together? This was a boat jumble 'not such a bargain after all', it was £1, but I was unable to find any supply of catalyst to go with it!
 
I've used epoxy up to 10 years old without a problem but it would depend on storage conditions temp etc.
Suggest you do a trial mix before you do anything important. Do not vary the mixing proportions as it simply won't work.
 
Re: Shelf life of epoxy ....

As Epoxy ages it darkens usually ... because of light acting on it. If kept in a sealed tin or container away from heat and light ... it should be ok for years ....

If you find you need more catalyst than before or recc'd - its rubbish and should be discarded - as extra catalyst weakens the final result.
 
It should last quite a while if kept away from light and cool.

Keep the catalyst well away from it. The method I use is to decant the amount I wish to use into a container and then decant from this into a mixing container, thereby preventing all possibility of contaminating the bulk stock.

Regards.

Alan.
 
Do a test laminate.
With west and sp,it is the epoxy left in the pumps that you have to watch out for..the pumps clog and deteriorate and so the calibration becomes suspect,meant to keep em cleaned regularly(or replace)
 
Epoxy resin has a virtually unlimited shelf life, although unlimited may be months, years or decades! Hardeners seem to be affected faster, and seperate out (the main liquid body goes honey coloured, and an oozy, yellowish paste seems to form within that).
At the risk of sounding like a teacher, a couple of points:
1. epoxy does not use a catalyst - it's a hardener, and is part of the result, whereas polyester and vinylester use a catalyst (typically mekp). In catalysed reactions, more catalyst causes a faster reaction, but the same does not apply here. The correct mix ratio for SP106 is 5 parts resin to 1 part hardener - changing the mix ratio does nothing other than result in an incomplete cure that will have less than optimum results. Simplistically, a cured molecule of resin comprises 1/6th hardener, and 5/6th resin - adding more hardener means there's extra hardener floating around, and the long molecular chains aren't formed as the chemist planned them.
2. epoxy resin often forms lumps when exposed to cold - it's crystalised parts of the resin, however they can easily be disolved by applying a little heat - sitting outside on a warm day covered in black plastic should be fine to return it to liquid.

Conact an SP Systems agent to buy some SP106 hardener, which is available in fast medium and slow cure rates.
 
thanks for all the answers, I won't bin it then, I will have another go at getting some hardener (at the time my area agent couldn't or didn't want to help).
 
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