You should keep Polyesters as cool as possible and OUT of direct sunlight (preferably out of light completely!). UV from sunlight causes a slow cure and will gel your resin over time. Heat will do the same thing! To get maximum shelf life you should store in a cool dark pleace.

Shelf life varies tremendously. First of all if its warm and in the sun its not going to last much over a week! However keep it cool and dark and we guarantee shelf life to 3 months after date of purchase. If kept very cool and in the dark shelf life can extend right up to 9 months!

That said we have tested resins at 9 months and found them to be still perfectly functional!

Again shelf life with Polyurethanes is much like that of Polyesters. Keep them cool and in the dark. However as a two part system with isocyanate hardener there is an additional care step to follow.

Iso is Hydrophyillic. That means it like water and will try to absorb it. So you must either purge the top of the bottle with a dry gas post use or replace the cap ASAP after use. Water poisoning will show as crystals forming on the top off the Part B Isocyanate and will eventually render the product useless.

Iso is also VERY frost susceptible! So under no circumstance allow it to fall under 5 Celsius. If it freezes its a throw away job. This applies to all PU systems be they resin or foam.

Reinforcement products require one careful step in storage to dividend an almost open ended shelf life. KEEP DRY!

Failure to keep chopped strand mat, chopped strands, carbon or kevlar dry will mean the resin will not wet out the glass substantilly reducing laminate strength. If your reinforcement materials get damp they will not work right and should be disposed of.

If you order full rolls of Chopped Strand Mat it is advised to store these on end in the box they were supplied in to prevent crushing of the roll along its length, which in some applications will cause issues with getting you mat to lie flat and true while laminating.