Process Development for Sandwich Core Structure PLA Thermoformed Objects

Polylactid acid (PLA) is a thermoplastic, aliphatic polyester derived from renewable resources, such as corn starch and other sugars. It has numerous environmental benefits, including a lower energy cost at the beginning of its life and biodegradability at the end of life, and it is used in food packaging.Sandwich core structures are composite structures of skin/foam/skin often used in airplanes to minimize weight while maximizing strength. The foam layer at the center of the structure lightens the weight, and therefore uses less material, while the skin provides a good surface layer and high strength to the part.Seattle Cup LLC has successfully created a sandwich core structure in PLA, allowing the use of less material with the same given amount of strength as current plastics used in food service and food packaging. The product can be made to have equivalent mechanical performance and similar appearance, and has the benefit of providing insulation from the foam core.On a single product scale, Seattle Cup can replace a 13.Sg polystyrene cup with a 7g PLA cup. The commercial applications for the technology are focused initially on single use disposable cups. The company’s long-term goal is to use this technology to replace all plastic food service and food packaging currently in use. The United States disposes of 32 billion pounds of plastic packaging annually, or 12.7 percent of municipal solid wastes (source: EPA website). Utilizing Seattle Cup’s technology,the 32 billion pounds of oil-based plastics Americans throw out could be replaced with 16 billion pounds of compostable plastic.