Magnetic Orientation of Polymers A Novel Technique of Controlling Birefringence

ABSTRACTMagnetic -field induced orientation of crystalline polymers recently reported by our group is briefly summarized and a possible application of this new phenomenon is presented. We have recently reported a new finding that crystalline polymers including poly(ethylene-2,6-naphthalate), isotactic polystyrene, isotactic polypropylene, poly(ethylene terephthalate), and paraffin align under a strong magnetic field during the phase transition from melt to crystal. We have assumed that some ordered structure, most likely liquid-crystalline-like structure, appearing transiently during the transition is responsible for this phenomenon. Aligned films were transparent and exhibited retardation of several hundred nanometers, suggesting a possible application to fabrication of materials demanded for optical use.