Structural analysis of oriented poly(ε-caprolactone) including CaCO3 particles with 13C solid-state NMR

Abstract

The results of a study of the relation between the oriented structure and drawn Poly(ε-caprolactone) specimens including CaCO3 particles and their dynamic mechanical properties are presented. The loss elasticity, E″, showed almost the same curve for both undrawn sheets and drawn sheets as a function ofCaCO3 content. On the other hand, the storage modulus, E′, of drawn sheets increased nonlinearly with increasing CaCO3 content, and their curve showed lower E′ values than those of undrawn sheets. By simulation of 13C CP NMR spectra of drawn PCL/CaCO3 sheets, both oriented and unoriented components were observed. The distribution parameter, p, of drawn PCL/CaCO3 sheets was 13°, which was larger than those (8°) of drawn PCL. Further, the fraction of the unoriented component increased with increasing CaCO3 content. Thus, adding CaCO3 particles into the PCL, the arrangement of the oriented component was disturbed and decreased. In addition, from the line shape analyses of 13C CP MAS NMR spectra, four peaks were obtained in not only undrawn sheets but also in drawn sheets of both PCL and PCL/CaCO3 compounds. Besides, structural change occurred at only drawn PCL/CaCO3 sheets. Therefore, the change in dynamic mechanical properties observed only for drawn PCL/CaCO3 sheets were strongly dependent on the orientational structure, which was formed under shear stress of the stretching drawn process. © 2001 John Wiley & Sons, Inc.