High Density Polyethylene is a common petroleum based polymer that is used in the production of bottles and piping.
The key characteristic of HDPE is its excellent strength to density ratio. HDPE's strength comes from the fact that its polymers are very linear, meaning that they pack together and interact with each other very strongly. As well as being very strong, HDPE is hard and opaque with moderate thermal stability.
HDPE has a melting temperature at around 120°C. HDPE has poor adhesion and is also subject to a lot of warping if cooled too rapidly. HDPE's poor adhesion and high warp make base layer adhesion particularly difficult however it may be improved by using a polypropylene plate.
If you are able to master 3D printing with HDPE then you can experiment with a filament that has an excellent strength to density ratio. Here at Filaments.directory you can select the right HDPE filament using our constantly updated list of suppliers and our comprehensive search tool!