FOAM CORES COMPRISED OF ONE OR MORE OF CROSS-LINKED POLYVINYL CHLORIDE (PVC), POLYETHYLENE TEREPHTHALATE (PET), STYRENE ACRYLONITRILE (SAN), POLYURETHANE, POLYSTYRENE, AND POLYMETHACRYLAMIDE (PMI), IN PRE-CUT LENGTHS AND SHAPES FOR USE IN FURTHER MANUFACTURING OF WIND TURBINE BLADES BY OTHERS; AND CORES FORMED PRIMARILY OF CELLULAR FOAM COMPRISING AT LEAST ONE OF POLYVINYL CHLORIDE (PVC), POLYETHYLENE TEREPHTHALATE (PET), STYRENE ACRYLONITRILE (SAN), POLYURETHANE, POLYSTYRENE, AND POLYMETHACR...