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The effects of the plasticizer poly(ethylene glycol)(PEG) on crystallization properties of equimolar poly(L-lactide)(PLLA)/poly(D-lactide)(PDLA) blends were investigated. Formation of the stereocomplex-type poly(lactide acid)(sc-PLA) crystallites was confirmed by Wide-angle X-ray diffraction(WAXD) and differential scanning calorimetry(DSC) analyses. Sc-PLA crystallites without any homochiral poly(lactide acid)(hc-PLA) formed, as the result of the incorporation of the plasticizer PEG(more than or equal to 10%(wt)) at a processing temperature(240 ℃). Moreover, when the MW of PEG reached 1 000 g × mol–1, the crystallizability of stereocomplex crystallites was the best. Isothermal crystallization kinetics further revealed that PEG could accelerate the crystallization rate of sc-PLA, with the optimum crystallization kinetic parameters being obtained at 10%(wt) PEG. Several crystallization kinetics equations were applied to describe the effect of PEG on the crystallization behavior of sc-PLA. The influence of PEG on the spherocrystal morphologies of sc-PLA was also investigated using polarized optical microscopy.
Formation of the stereocomplex-type poly (ethylene glycol) (PEG) on crystallization properties of equimolar poly (L-lactide) (PLLA) / poly (D-lactide) (PDLA) blends were investigated. (sc-PLA) crystallites was confirmed by Wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC) analyzes. Sc-PLA crystallites without any homochiral poly (lactide acid) the result of the incorporation of the plasticizer PEG (more than or equal to 10% by weight) at a processing temperature (240 ° C). Moreover, when the MW of PEG reached 1000 g × mol- 1, the crystallizability of stereocomplex Isothermal crystallization kinetics further revealed that PEG could accelerate the crystallization rate of sc-PLA, with the optimum crystallization kinetic parameters being obtained at 10% (wt) PEG. Several crystallization kinetics equations were applied to describe the effect of PEG on the crystallization behavior of s c-PLA. The influence of PEG on the spherocrystal morphologies of sc-PLA was also investigated using polarized optical microscopy.