Dear Esraa Zalama, I think sodium azide is usually used for sterilization. Also Ultrasound may be used instead, but with some care as it may be degrading for some polymers. My Regards

Ethylene Oxide sterilization is routinely used in healthcare. You can do a little bit of literature search to check if people have used it to sterilize scaffolds or polymers similar to your.

Azide does not sterilize.

Gamma irradiation and, as Srujan noted, ethylene oxide are options but you'll need to work with a treatment supplier.

Are these materials autoclave stable?

Long shot - maybe B- propiolactone