A filler material of a thermoset resin of a diacid/polyol, such as PGS is provided. The filler useful in forming composites, such as those in which the filler and a resin matrix are of the same material to provide a homogenous polymeric composition. Composites in which at least one of the matrix, the filler or both are PGS are also provided. Methods of forming such filler materials and composites are also disclosed. The composites allow extrusion process to form articles from materials that would not otherwise be capable of being extruded.