Hi,
If you're talking about ABS,
here is a link on what/where to get. You should glue it together as hot glue will only last for a short while and may come off in extreme heat. To hold the glued pieces together, you will need some shop clips or vice of different sizes and strengths and use some sort of padding in between the plastic and the clips. Most often if padding is not used while using clips or vices, during the gluing process, the plastic heats up therefore it becomes malleable and the clips or vice will leave an imprint on the plastic. Hope this helps!
