Stereocomplex crystallization processes of poly(L-lactic acid) and poly(D-lactic acid)
What is it about?
The objective of this study is to investigate the effect of shear flow imposed prior to crystallization on higher-order structure formation and acceleration of high melting point and toughness stereocomplex crystals growth of PLLA and PDLA blends using a wide spatial scale analysis and viscoelastic measurements. The density fluctuations of the 100-nm scale were observed prior to nucleation. These density fluctuations grew with time and the intensity increased with increasing shear rate. Furthermore, the results revealed that the PLLA and PDLA chains were only partially interpenetrated; consequently, stereocomplex crystals could grow only in the mixed PLLA/PDLA phase. The correlation length of density fluctuation prior to nucleation was strongly dependent on the mixed phases.
Why is it important?
The stereocomplex is much higher melting point and toughness comparing with the norminal alpha- crystals of poly(L-lactic acid) or poly(D-lactic acid). To investigate the structural formation process of stereocomplex crystallization is quite important for science, engineering and envioronment.