Multi-layer thermoformed polymeric foam articles and methods

A method of forming a foam article comprising:

• providing a multi-layer precursor sheet including multiple layers and a polymer foam layer, wherein the polymer foam layer is sandwiched between two solid polymer layers;
• thermoforming the multi-layer precursor sheet to form a thermoformed article including multiple layers, wherein the thermoformed article is a container;
• immediately filling the container with food contents;
• and
• immediately sealing the container,
• wherein one of the layers of the thermoformed article is a polymer foam layer having an average cell size of less than about 100 micron and having a density of reduction between 5% and 50%, and
• wherein the thermoformed article has a density equal to or less than a density of the multi-layer precursor sheet.