All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
It is permissible to perform prayer on mats made of plastic, and to wear a cap made of plastic as long as wearing it does not involve imitation of the disbelievers or dissolute people. Plastic is in principle a pure material, and we do not know any scholar who gave a Fatwa prohibiting or disliking its usage. Also, scholars stated that it is permissible to perform prayer on any pure item.
Allaah Knows best.