Curing Reaction, Thermal and Mechanical Properties of Low-Temperature Elastic Epoxy Resin

As the desired underfill material for the application in the infrared focal plane detector (IRFPA), the low-temperature epoxy resin glue with tetrahydrofuran (THF) copolyether modification was prepared by mixing modified epoxy resin and a certain amount of curing agent. The thermal and mechanical properties of the cured samples were analyzed using dynamic mechanical analysis (DMA) with different testing modes and temperature condition. Discrepancies of elastic modulus were found through the liner fitting to strain-stress curves, which were measured by tensile loading fixture with a gradually increased static force. As a dynamic test, temperature scanning mode was employed to characterize the glass transition temperature (T-g) of final samples, with which related data ranged from 30 to 50 degrees C was indirectly obtained from the value of damping parameter peak position. DMA methods could be efficiently used to simulate the practically changed temperature environment and timely record the testing data, which is significant for studying the chip failure mechanism in IRFPA.