Polylactide and polylactic acid (PLA) resins are the second family of bioplastics resembling conventional clear commodity plastics with a good aesthetics (gloss and clarity), but with some shortcomings, such as deficient heat-deflection temperature, long/slow crystallization time, and brittleness, which have limited its use in injection molded products. However, their formulation and plasticization sufficiently improve their features allowing more and more applications.
Industrialization of PLA takes the conventional ways of industrial plastics, optimization of the properties by compounding with additives and blending with other (bio)plastics, processing using standard methods. PLA considerably vary the one from the other according to the balance between D and L forms. Its behavior can evolve from a rigid plastic up to an elastic material with melting points up to 200°C. As for conventional plastics, producers market ready-to-process grades processible by conventional methods. It is also possible to blend PLA with conventional plastics and to formulate customized recipes with a lot of additives from natural or synthetic origin as diversified as melt strength enhancers, impact improvers, stabilizers, plasticizers, colorants, clarifiers, antistatics, antifogs, barrier treatments… Of course, additives must preserve the advantages of the bio-plastic. Their processing must use standard methods and the cost must be competitive. Alloys and composites also play essential roles.
Research and development works are intensive and consequently many patents concern compositions based or containing PLA.
PLA is receiving significant consideration as an environmentally friendly resin, being biomass-derived resins classified as a renewable resource, requiring a relatively small amount of energy for production and generating a relatively small amount of carbon dioxide per unit weight when incinerated.
NatureWorks LLC was the primary producer of PLA in the United States but some other companies are developing PLA manufacturing.