Gamma Radiation and Thermoformed Polymers

The rise in thermoformed plastic device production and use in the medical arena is accompanied by a complex issue—because thermoformed plastics can be comprised of a variety of different combinations of polymers, not all thermoformed plastics react to gamma radiation the same way. In fact, some thermoformed plastics will lose their structural integrity, degrade, or exhibit discoloration as a direct result. Still, gamma radiation is quick, cost-effective and can even be used on some types of pre-packaged equipment. 

Determining Appropriate Materials for Gamma Sterilization

Many materials yellow as a result of gamma radiation, although some are more resistant than others. If glass-fiber is present in a polycarbonate composite, the yellowing effects of gamma rays are significantly lessened.  Materials that are dark in color also will not show much color change, although they still may exhibit degradation. 

Understanding how different materials react to gamma radiation is helpful when determining if gamma radiation is appropriate for a specific application. Although much depends on the exact make-up of a specific polymer, there are some general rules that may be useful when considering the process. Medical Device & Diagnostic Industry Magazine offers the following tips.

When in doubt about a material’s ability to undergo gamma sterilization, information is often available from the polymer manufacture. Having a better understanding of a material’s components may help in deciding if gamma radiation is an appropriate choice.