Polymer Crystallization Viewed by Magnetic Alignment

Abstract

Abstract. Observation of the magnetic alignment in polymeric materials provides a unique means to detect and analyze anisotropic structures, or mesophase, existing in polymer melts and/or forming during phase transitions because the anisotropic structures usually exhibit diamagnetic anisotropy which is a driving factor of the magnetic alignment. In this chapter, we first describe general concepts of diamagnetic alignment, followed by an example of the detection and analysis of a mesophase occurring during crystallization from melt. Also, mesophase existing in a melt is demonstrated by means of magnetic alignment. Discussion is given about a possible alternative mechanism of magnetic alignment on the basis of the orientation dependent shift of melting point under magnetic fields.