Yes, acrylic is a good choice for secondary glazing.
The benefits of secondary glazing include increased thermal and sound insulation as well as extra security. Acrylic’s light weight and flexibility make it very easy to install yourself at home and the extremely high light translucence means there will be no noticable reduction in light entering the room.
For extra security consider using polycarbonate sheeting which is roughly 30 times stronger than acrylic and is also ideal for secondary glazing.