Recent weather conditions have brought us hot humid days well ahead of our "normal weather" for this time of year.  These hot humid conditions definitely affect 2-part and 1-part adhesives and sealants.  Here are a few reminders to help you with your manufacturing / aseembly processes.

2-Parts:  These adhesives cure due to a chemical reaction between the 2 components.  As the temperature rises in your facility or out in the field (service work and field repairs), the open time, working time, gel time, and cure time are all accelerated.  The general rule of thumb is that these times are cut in half for every 10°C/18°F increase in temperature above 24°C/75°F.

If your 2-part is a polyurethane, you should be taking exra care to protect the moisture sensitive material.  Purging containers after opening them before re-closing them with an inert gas that is heavier than air like dyr nitrogen or argon will help you maximize your shelf life.  Moisture exposure can cause bubbles to form.  You should also make sure any desiccant dryers are changed as needed.

1-Parts:  These moisture curing adhesive sealants will benefit from the additional humidity by curing faster.  That means they will also skin over more quickly.  Make sure you're getting parts assembled before this skin develops to get good adhesion.  If you're using 1-part polyurethanes, you'll need to make sure you purge containers before re-closing them with dry nitrogen or argon to maximiize their shelf life.  You may also notice dispense heads clogging due to this accelerated skinning.

As always, if you have any questions, please contact us for technical assistance.