What Does PLA Stand For?

If you own a 3D printer, you’ve probably seen these three letters – PLA. That stands for polylactic acid or polylactide and it’s a versatile thermoplastic that’s great for making objects with your 3D printer. It’s also made from renewable plant resources too, unlike many other thermoplastics out there that rely on petroleum.

Here we’ve gathered everything you need to know about PLA. If you’re asking what it stands for, you should benefit from knowing how it’s made and why it’s useful too. We have covered the production process, its sustainability, how it is used in 3D printers, and the main manufacturers of PLA filaments.

PLA Production

While mainstream 3D printing is new, PLA has been around since the 1930s. It was invented by Wallace Carothers, an American chemist who worked for DuPont, but it was just part of polymer research. Carothers worked on other projects, like nylon and neoprene, instead. The first commercial production of PLA was in the 80s, by food corporation Cargill.

That makes sense, given how polylactic acid is created. To create PLA, a source of carbohydrate is required. This is often corn starch but other sources can also be used, like sugar cane or tapioca roots. From there, the starch is separated and mixed with either acid or lactic monomers. This makes the starch break down, where it becomes dextrose, a form of glucose also called D-glucose sometimes.

As glucose ferments, it produces L-lactic acid. The technical name for this is a non-Newtonian pseudoplastic, which is where its consistency changes depending on how much stress is applied to the material.

Now in its raw form, the PLA is granulated and sold. If you get PLA filaments for your 3D printer, the manufacturers get the natural PLA pellets and then mix them with additives that change color or how the PLA reacts to high-heat environments. Then the grains are melted into a stringed plastic, to be placed into your 3D printer.

PLA Sustainability

As we said, PLA has a reputation for being sustainable because it’s made from plant-sourced natural ingredients. That said, there is some confusion over how sustainable PLA can be. For example, it’s a common misconception that sustainability equals biodegradable, which isn’t the case.

PLA can decompose under certain conditions, like industrial-grade composting, but otherwise, it’s not biodegradable. In other conditions, it can linger around for 100 years, during which it will pollute the area around it like other plastics. The term biodegradable is attached to PLA for commercial purposes but you should be aware that it is not in some contexts. If you’re environmentally conscious when printing, there are still ways to dispose of excess PLA safely.

PLA Printing

The fact PLA is renewable and (possibly) biodegradable is one of the reasons it has become so popular for 3D printing. It’s also easier to work with, so the droves of beginners who are starting out at 3D printing tend to prefer it over the more technically difficult materials.

For example, PLA melts at just 180 degrees Celsius because it’s a semi-crystalline polymer that doesn’t withstand heat as well. ABS filaments, on the other hand, will start melting somewhere between 200 and 250 degrees Celsius. The lower melting point of PLA makes printing easier because you don’t need to use a closed chamber or a heated printing bed to achieve such high heat levels.

Of course, the fact PLA is less stable under heat also means it’s a lot more viscous once it has melted. Where print head clogging is a possibility, you should be careful when printing with PLA and unclog it when necessary. If you make sure the head is clear before each print and clean it afterward, you shouldn’t have too much trouble.

PLA isn’t as flexible as ABS filament, however. Generally, PLA is the perfect beginners’ material and it works for smaller-scale, uncomplicated prints. No matter your proficiency with 3D printing, it’s wise to keep some around for those small prints that aren’t worth breaking out the more flexible, expensive filaments. Where a project demands a more rigorous filament, you’d be better off trying others instead.

Lastly, PLA is also popular because it’s very easy to work with once the print has been completed. PLA works very well with acetone treatment and it’s also softer when sanded down, making it much easier to smoothen and shape.

If you do a lot of post-processing, PLA is a great material to work with and you won’t have any trouble breaking off supports. Some printing trays can stick to the first layer of PLA prints, so many recommend adding tape to your tray to avoid this.

PLA Manufacturers

PLA is one of the most popular 3D printing materials that are in use today. That means there’s no shortage of manufacturers. If you like what you’re hearing about PLA, you may be on the lookout for providers near you. Thanks to the Internet, you should be able to order PLA filaments and get them delivered to your door.

You can get PLA filaments from NatureWorks – an American company that specializes in biopolymers. In Europe, WeforYou develops PLA filaments in Austria while Corbion creates PLA and other high-performance resins in the Netherlands and sells filaments through their Luminy brand.

The price you’ll pay for PLA filaments will depend on several other factors; color included. If you’re getting PLA-hybrid filaments, where conductors, wood, or other exotic materials have been added, will make the filaments more expensive. While the price may fluctuate and is subject to other factors, you can stay confident that PLA is less expensive than ABS, ASA, nylon, and other popular alternatives.

Final Thoughts

With that, you should know everything you want to know about PLA. Not only do you know what it stands for now, but how it’s made, how it’s used, and how it compares to other printing filament materials.

Michael Moore