Do not use Super Glue (Cyanoacrylate). Super Glue reacts chemically with acrylic, causing the edges to "craze" or fog up white permanently. It creates a brittle bond that will fail. To fix Plexiglass, you do not glue it; you weld it.
The material has snapped. A clean break or a shatter requires more than surface treatment; it requires molecular bonding. how to fix plexiglass
Plexiglass repairs are feasible for scratches, small cracks, and chips using solvent welding and abrasive polishing. However, repairs are never optically perfect. For high-clarity or load-bearing applications, replacement is the preferred solution. Do not use Super Glue (Cyanoacrylate)