To ensure that residual polymer does not degrade when stored in the cartridge and to protect from moisture it is recommended to remove all unmelted polymer from the cartridge. Then place the plunger back in the cartridge, backfill with an inert gas such as nitrogen, wrap the ends in parafilm, and store at -20 °C. The stability of the thermoplastic utilized must be considered, the heating and cooling process within the cartridge during printing may affect how the thermoplastic melts the next time it is utilized. For these reasons, it is recommended to only print with the necessary amount of thermoplastic granulate for your experiments.