The present invention is directed to novel polystyrene foam reduction recycling compositions and methods that solve the volume problem of recycling polystyrene foam materials while simultaneously allowing the easy and inexpensive shipment of the foamed materials after reduction in volume by use of one or more dibasic ester compositions in combination with one or more low heat based mechanical extruders. The methods of the present invention are applicable to all types of expanded or foamed polystyrene materials known to those of skill in the art.