Introduction:
Polylactic Acid (PLA) is a biodegradable thermoplastic that is commonly used in 3D printing. It is derived from renewable resources such as corn starch, cassava roots, or sugarcane which makes it an excellent alternative to petroleum-based plastics, as it is biodegradable and has a lower environmental impact.
Production and History:
Wallace Carothers, a scientist at DuPont, made the initial discovery of PLA in 1932. Yet, it wasn't until the 1990s that scientists started to take the findings seriously. Now that biotechnology has advanced and creative manufacturing techniques have been developed, it is possible to produce PLA on an industrial scale.
PLA is created by fermenting sugars that come from corn, sugarcane, or other plant sources. The next step is fermentation, which transforms sugars into lactic acid. Following up in the polymerization of the lactic acid is ring-opening polymerization, which includes the opening of cyclic ester molecules to produce PLA chains that are linear in nature. Some more processing is needed to create pellets which then get turned into filament.
Properties:
PLA has several unique properties that make it an excellent choice for 3D printing. One of the most notable features of PLA is its biodegradability, unlike petroleum-based plastics, PLA will break down over time and is not harmful to the environment if done right.
This is only possible in industrial recycling plants under precise and controlled settings tho. It will not break down in home compost.
PLA is a strong, rigid plastic that is easy to print. It has good layer adhesion and produces prints with a smooth surface finish. It also features a relatively low melting temperature, which makes it easy to print on a wide range of 3D printers. In addition to that it has low warpage.
Regarding its physical properties, PLA is a solid, rigid material with good resistance to impact and deformation. Due to its low level of toxicity, it may be used safely in both medical applications and food packaging.
Machining:
PLA is easy to machine and can be sanded or painted to achieve the desired finish. However, PLA is not as strong as other thermoplastics and is prone to warping if exposed to high temperatures which means it is important to avoid placing PLA parts in high-temperature environments.
Post Processing:
Sanding and painting can be used to achieve the desired finish. Special attention must be aimed at not heating up the material too much as it will deform easily.
Safety:
PLA is a non-toxic and safe plastic to use. However, as with any plastic, it is important to take appropriate safety precautions when printing with PLA. It is recommended to print in a well-ventilated area, as PLA can release fumes when heated. It is also important to avoid inhaling or ingesting any dust or particles that may be generated during printing or post-processing.
Conclusion:
PLA is an excellent choice for 3D printing, as it is bio based, super easy to print, and produces high-quality prints. It can be used to create a wide range of objects and products as long as its weaknesses are accounted for. As more attention is given to environmental concerns, PLA and other biodegradable plastics are becoming increasingly popular in the 3D printing community.
