Determination of Anisotropic Diamagnetic Susceptibility of Polymeric Fibers Suspended in Liquid^*

Abstract

Anisotropic diamagnetic susceptibilities of polymeric fibers in liquid suspensions determined by means of the method proposed recently by us were compared with those obtained by other methods including superconducting quantum interference device (SQUID) and magnetic torque meter. Poly( p -phenylene-2,6-benzobisoxazole) (PBO) fibers and carbon fibers (CF) were used for the measurements. Both fibers exhibited positive diamagnetic anisotropy, i.e., χ a ≡χ // -χ ⊥ >0, where the parallel direction is taken as the fiber axis. The values of anisotropic susceptibilities determined by these three different methods were in good agreement with each other, demonstrating the usefulness of the proposed method for the measurement of a single fiber.