The glue will depend on the type of plastic.
Normal cyanoacrylate (super glue) doesn't really work on plastics. It might stick, but the repair is often brittle.
Butanone (better known as plastic cement and plastic weld) works great on ABS and other styrenes, but only those.
Contact adhesive on the other hand can stick non-porous plastics to porous surfaces. But won't hold two non-porous surfaces together very well.
You might be best with a two-part epoxy resin, such as Araldite, or a two-part super glue, such as Loctite All Plastics Superglue.
Last edited by little_pob; 28th Mar 2014 7:04pm.