Winter Weather Advisory : What are the effects of cold weather on urethane, silicones, epoxies, and latex-based materials?
Cold weather will not permanently harm urethane, silicone or epoxy materials. It can cause these materials to thicken and separate. If you try to use the material while it is too cold, it will not cure.
If you suspect your materials are cold, allow them to reach room temperature (at least 73°F / 23°C) in the containers before opening. Depending on how long the materials were exposed to the cold, it can take several days to bring them up to 73°F (23°C). Pro Tip: During cold winter months, bear in mind how long material may have been sitting in an unheated delivery truck.
Once the material has reached room temperature...

Urethane RubberOpen Part A & B containers and mix thoroughly (3 minutes) with a clean flat edge stirring paddle (different sticks for each Part to prevent cross contamination) before dispensing into a mixing container.


Silicone Rubber – Open Part A and mix thoroughly (3 minutes) with a clean flat edge stirring paddle before dispensing into a mixing container. For 100A:10B by weight systems (e.g. Mold Max™, Smooth-Sil™ series) vigorously shake the Part B container. For 1A:1B by volume systems (e.g. OOMOO™, Mold Star™, Dragon Skin™ series), open Part B and mix thoroughly (3 minutes) with a clean flat edge stirring paddle before dispensing.
Epoxyfollow the standard pre-mix instructions located on the product's technical bulletin.
    Urethane Resin – Vigorously shake both Part A & B containers before dispensing. Urethane systems with fillers (e.g. Smooth-Cast™ 385, TASK™ 18, Feather Lite™) may need to be opened and thoroughly mixed (3 minutes) with a clean flat edge stirring paddle (different sticks for each Part to prevent cross contamination) before dispensing into a mixing container.
    • Note for Simpact 60A and 85A: These materials may congeal if exposed to cold temperatures. To reconstitute, Part A & B must be heated to 90°F (33°C) then thoroughly mixed to an even consistency.
    Latex Based Products
    Forton™ and duoMatrix™ acrylic latex polymer systems cannot be allowed to freeze. If they freeze, they are permanently unusable.
    Keep it off the Concrete Floor
    Store products off of cold concrete floors. Even in a heated shop, concrete will cool 5-gallon pails or even gallon buckets left in cardboard boxes to a point the material may cure slowly or not work at all. Store containers off the concrete floor on a pallet, foam board, etc.