@Ann: Many of the comments from your recent article about soy-based polyurethane foam would apply to this material. In fact, corn-based PLA is significantly more objectionable in terms of its impacts on the environment and the global food crisis.
Furthermore, if the goal is to increase the strength, stiffness, and heat deflection temperature of injection molded plastics, it's already possible to do so using traditional mineral fillers such as talc and calcium carbonate.
The mechanical properties of these new PLA blends look roughly equivalent to what could be expected from a talc-filled PC/ABS. The main selling point appears to be the ability to put a USDA "bio-based" label on them.
Of course, the role of the USDA is to expand markets for U.S. agricultural products, which the use of bio-based plastics certainly does.
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