Plexiglas is a brand name or trade name of Acrylic made by Roehm ®. Plexiglas Acrylic is especially known for its longterm optical + structural propperties.
Acrylic Sheets and Acrylic Panels can be thermoformed to obtain Curved Shapes. Thermoforming is successfully used for Aquarium Tunnels and various Acrylic Displays.
Both acrylic and polycarbonate are transparent thermoplastics. For all their similarities, there are differences in the areas of optical stability + impact resistance.