Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Epoxy Cure Time
Name:   Naomi W.
Status:  student
Age:  15
Location: N/A
Country: N/A
Date: 2000

Why does epoxy glue take less time to harden when in the sun and if i wanted to do an experiment on this, what apparatis would I need?


The curing time of some epoxies is affected by ultraviolet (UV) light. Sunlight is a source of ultraviolet light. You might like to ask your dentist about those materials because UV curing resins are used in modern dentistry.

In addition, epoxy curing time is affected by temperature . The warmer the mix, the faster the cure. It's likely that the sunlight warmed the mixture. It will be tricky proving this with a thermometer because the thermometer will become trapped in the hardened resin. Perhaps you could make small batches of the mix and put it into a soda bottle cap that's sitting in a small dish of water. You could put the thermometer into the water next to the cap. Be sure to cover the cap so light cant strike the mixture. Otherwise you won't know whether it's the heat or light that is affecting the cure time.

Good luck with your experiment.


Click here to return to the Chemistry Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory