Ecofriendly substitutes for Polystyrene

10-Oct-09

Products made from Polystyrene can be made with eco-friendly starch from potatoes, wheat or corn, instead of from petroleum, in turn, reducing dependence on petroleum. Gregory M. Glenn from Agricultural Research Service (ARS) and Simon K. Hodson collaborated to develop two recent technologies. Both approaches yield strong, durable, and versatile biofoams that look like familiar polystyrene foam goods. Like conventional foams, the biofoams can be manufactured to a range of densities and can be die-cut or molded into a seemingly limitless array of shapes, sizes and thicknesses. Both patent-applied-for technologies rely on an extruder to heat and mix starch and other all-natural compounds. At various points in the process, the beads puff and expand, such as when they are put into the cavity of a heated mold to press them into the desired shape. Expanded beads eventually touch one another, creating a strong matrix that's much like the bead matrix of polystyrene foams. The biofoams aren't waterproof, but a moisture barrier, made from plant sources such as corn, can be added, ensuring that the finished foam is still derived exclusively from renewable, biodegradable resources.