PVA (Polyvinyl Alcohol) is not only non-toxic and biodegradable but it is also water soluble, so it can only be used as a support material in printing as it will dissolve when it comes in contact with water. It has to be kept dry prior to printing and needs to be sealed with a desiccant to store it.
The objects look translucent after printing and have a yellow tint to them. PVA is generally used with dual extrusion printers as one extruder prints the primary material such as PLA and the second extruder prints this dissolvable filament.
It is crucial that the printing temperature for PVA does not exceed 230C. Once the temperature, bed height and speed are set, the level of printing difficulty becomes easy.
It provides support to models which require intricate detailing and over hangings since it is water soluble.