As the conversation around sustainable alternatives to petroleum-based plastics escalates, polylactic acid (PLA) has gained popularity and attention. 
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⁠In this blog, we break down the unique and notable characteristics of PLA.
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⁠What are PLA resins?

⁠Polylactic acid (PLA) resins are made from corn and sugar cane. The starch (glucose) is fermented to produce lactic acid, which is then chemically reacted to produce a compound called lactide, which is then polymerized. Its molecular structure is represented as CH₃ CHOH−COOH.
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⁠While many think the terms polylactic acid and polylactide are the same, there are slight differences:
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⇒ Polylactic acid: Overall term for this type of biopolymer
⁠⇒ Polylactide: Specific form of PLA made by lactide polymerization⁠

⁠⁠PLA essentials

⁠There are countless reasons why using PLA resin is beneficial. In addition to being a bioplastic, PLA density and yield strength of PLA are relatively high. However, the PLA melting point and impact strength are low, though materials to improve these areas are under development.
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⁠Is PLA actually plastic? 

Absolutely! All plastics, whether petroleum or bio-based, are made of polymers (long chains of repeating molecular units); PLA has repeating units of lactic acid. 
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⁠As the demand for renewable resources grows, so does the use of polylactic acid. These resins are typically extruded into PLA film — lightweight, versatile sheets used for anything from medical applications to consumer goods and more. In fact, PLA packaging is ideal for short-term needs like food packaging because it is non-toxic, moisture resistant and can be attractively designed. 
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⁠Despite the popularity of PLA packaging, perhaps the biggest use of PLA resin is for 3D printing. Thanks to limited warping, smooth surface finish, and variety of blends and colors, PLA film is easy to print. Plus, it is cost-effective and easily available, thanks to its renewable resource base.
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⁠Is PLA biodegradable?

⁠PLA is a biomass plastic and a biodegradable plastic. While biodegradable PLA has less environmental impact, it does not decompose naturally when left in the environment. It is decomposed (hydrolyzed) by fermentation heat and moisture in compost and converted to microorganisms into carbon dioxide and water.
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⁠PLA composting is best handled in industrial facilities with high temperatures and controlled humidity. In this setting, it can decompose within 90-180 days. Composting PLA at home is not ideal (or recommended) because the necessary temperatures cannot be achieved and may take years to break down. 
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Polylactic acid: A sustainable shift

PLA still needs to overcome some issues, and it is not yet as commonly used as petroleum based plastics, but the market is expected to expand in the future as it helps reduce the environmental impact.