Highly improved crystallization behavior of poly(L-lactide) induced by a novel nucleating agent: substituted-aryl phosphate salts.

In this work, a novel nucleating agent (NA) based on substituted-aryl phosphate salts was introduced into poly(L-Lactide) (PLLA). The nonisothermal and isothermal crystallization behaviors of nucleated PLLA samples were investigated through differential scanning calorimetry (DSC), wide angle X-ray diffraction, and polarized optical microscope (POM). Furthermore, the effect of annealing treatment on the cold crystallization behaviors of nucleated samples was also investigated. The results show that the crystallization of PLLA, whether for the melt crystallization (including nonisothermal and isothermal crystallization process) or for the cold crystallization (including the cold crystallization occurring during the DSC heating process and during the annealing process), is greatly dependent upon the content of NA. At relatively lower NA content (≤0.1 wt%), the nucleation effect of NA is inconspicuous, however, at higher NA content (≥0.2 wt%), it exhibits great nucleation effect for the crystallization of PLLA. Further results show that the double endothermic peak of PLLA depends on the temperature applied for the crystallization. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]