Investigation of the accelerated thermal aging behavior of polyetherimide and lifetime prediction at elevated temperature

Fire-protective clothing are manufactured using heat and flame resistant fibers that are made of high-performance polymers. These polymers exhibit a gradual reduction in their performance after long-term exposure under various aging conditions. This study investigates the thermal aging behavior of a high-temperature resistance polymer, polyetherimide (PEI), at elevated temperatures in air. Changes in the ultimate tensile strength (UTS), glass transition temperature, and surface properties are observed. In addition, infrared spectroscopy identifies chemical bonds in PEI being consumed because of chain scission. Applying the time-temperature superposition principle to the UTS data gives an activation energy of 112 kJ mol(-1) for the effect of thermal aging on the mechanical strength of PEI. This value is similar to what has been reported for fire-protective clothing fabrics, which opens the possibility to use PEI as a sensing material for the development of end-of-life sensors for fire-protective fabrics.

Automated summary

This study investigates the thermal aging behavior of a high-temperature resistance polymer, polyetherimide (PEI), at elevated temperatures in air. Changes in the ultimate tensile strength (UTS), glass transition temperature, and surface properties are observed, with an activation energy of 112 kJ mol(-1) identified for the effect of thermal aging on the mechanical strength of PEI. These findings suggest the potential use of PEI as a sensing material for the development of end-of-life sensors for fire-protective fabrics.