Polylactides (PLA) or polylactic acids represent a relatively new group of thermoplastics for packaging applications obtained from renewable resources. In extensive tests the functional and thermoforming properties of PLA are compared with those of other polymers. They are a biodegradable/compostable polyester manufactured from plant based resources. At 60°C and relative air humidity of 80% PLA will degrade completely after 60 days.
PLA's properties make it suitable for various thermoforming applications, particularly cups for cold bevarages and trays for fruit and vegetables. To produce high-molecular PLA, a process is used that is sustainable, solvent-free, and environmentally friendly.
PLA can be obtained from cassava, corn, maize, sugar beet, sugar cane, wheat, or agricultural byproducts containing natural plant sugars.
Although PLA has been known for more than a century, it has only been of commercial interest in recent years, in light of its biodegradability.
While PLA is one of the most promising bio-basedplastics, its main disadvantages are high price and unsatisfactory mechanical properties.
My understanding is that thermoforming is however only really utilized for sheet-based PLA material with essentially non-convex configurations. Also, it tends to degrade over 60 degrees celsius.
I wonder how this process and its output differs step-wise, limitation wise, and in terms of resulting material's mechanical properties. From the sounds of it, it's essentially a layering process and too early to judge limitations, though a small temperature range could perhaps be expected.