noun which may take the genitive case particle 'no', noun
plastic; made of plastic
Used as a noun or with の to modify another noun, indicating the material is plastic.
この容器はプラスチック製です。
This container is made of plastic.
プラスチック製のスプーンをください。
Please give me a plastic spoon.
プラスチック is the material itself; プラスチック製 explicitly means 'made of plastic'.
Compound of プラスチック (plastic) + 製 (made of).