Preparation of Poly(lactic acid) Films in a Magnetic Field and their Microstructure

Abstract

Poly(L-lactide) (M_n = 1.0 × 10⁵) (PLLA10) films and crystalline PLLA/amorphous poly(DL-lactide) (M_w = 1.0 × 10⁴) (PDLLA1) blend films (PLLA10 PDLLA1) were prepared in a magnetic field and thermal annealing. The small-angle X-ray scattering peak of PLLA10 cast films was at q = 0.24 nm⁻¹. That is, the peak is corresponding to the long-period of the PLLA10 crystals. On the other hand, the SAXS peak of PLLA10 PDLLA1 cast films was at q = 0.33 nm⁻¹. This means that the long-period structure of PLLA10 changed with increasing the volume of amorphous regions in blend films. We thus suggest that such amorphous regions play an important role in preparation of PLLA oriented films in an applied magnetic field.