Question: The concept of using renewably sourced biodegradable 3D printing stock is brilliant. In the chat I heard that PLA can come from cornstarch - the stuff you can cook with! How does the process work? What does the PLA look like? Is it water-resistant?

Anthony Newell answered on 13 Nov 2019: last edited 13 Nov 2019 1:07 am

PLA is a renewably sourced and biodegradable plastic commonly used in 3D printing. It is made from cornstarch or any other starchy vegetable like potatoes. PLA stands for polylactic acid, which means that the plastic is made up of a chain of lactic acid molecules. To make the plastic, lactic acid is produced from cornstarch by a process called fermentation. In fermentation, the starch is broken down into lactic acid by bacteria. The lactic acid molecules are then joined together by a second chemical process to form the polymer, PLA. PLA looks like any other plastic we use. It’s most similar looking to the plastic used in water bottles, called PET. It and can be made into many different colours for 3D printing. You can even get transparent PLA depending on your application! PLA is water-resistant and can also be used for biodegradable cups which can even be composted. Not only is it biodegradable, but it is also recyclable. Many 3D printing users have even generated plastic stock filament from old PLA parts. PLA is a very useful material that makes 3D printing a sustainable option for users worldwide.