PLA-filament is processed out of „Poly Lactat Acid“. On the chemical side PLA is what the name says: polimerized lactic-acid. Polymerization means to bind single (monomeric) carbon-molecules to long chains.
Milk in PLA-filament?
Chemically: yes! PLA is very similar to chunks of sour milk.If you take the chunks and dry them, yo get PLA. PLA is a plastic wth thermoplastic properties. PLA is getting soft at temperatures about 60 °C and flowable at about 150 °C.
Our PLA is made of cornstarch.The cornstarch is polymerized through fermentation with lactic acid bacteria. We know them from our food. They come in handy when fermenting yogurt, buttermilk or white beer and they produce the typical milk-sour taste.
As you can see, PLA is a real biological and green plastic made of renewable resources. . If PLA isn´t recycled or burnt (to produce electricity) but is thrown away in nature, it gets brittle (caused by UV-light) but it does not fall apart. It stays in polymeric state and can outlast for a long time which leads to the well known problems with plastic garbage in the environment.
PLA can be rotten and composted in specialized industrial composters using efficient bacteria and controlled environmental properties. They split PLA into its components and
PLA-Filament in your 3D-printer
PLA is a good material for 3D printing because it behaves very kind while printing and gives the oppurtunity of printing designs other materials aren´t capable of. Printed layers stick together very well which means, that you can print very robust things. Another big advantage is that you can cool PLA actively while printing. Active cooling blows air right tot he just printed filament. This way the filament stays in shape and cannot deform anymore.
Using the active cooling system you can print bridges and overhangs which are impossible to print with ABS. Active cooling also comes in handy, when you have in mind that warping is minimized by using active cooling. Warping is the effect you see, when you printing bends up at the edges. This happens, because of inconsistent cooling – the print is hotter in the middle than it is on the edges. Plastic is always deforming a little when it is cooling and that produces tension within the printed object. These problems can be avoided widely by printing with active cooling.
PLA-filament is a nice material for 3D printing. It is non-toxic, relative odourless and can be printed very well. The only limitations PLA has is ist low resistance against temperatures and low impact resistance, because sometimes softer materials have a better impct resistance.