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In this study, the blend of polycarbonate (PC)/poly(L-lactide) (PLLA) (70/30) was prepared through the conventional extrusion-injection-molding process. The morphology of the blend was characterized using scanning electron microscope. Both differential scanning calorimetry and wide angle X-ray diffraction were used to investigate the crystallization behavior of PLLA component in the blend. The mechanical and thermal properties of the blend were comparatively investigated, and the hydrolytic degradation ability of the material was also evaluated. The results show that the dispersed-PLLA particles are in the amorphous state in the PC matrix. Although the blend is immiscible, the rigid PLLA particles exhibit the toughening and reinforcement effects on PC simultaneously. Specifically, the heat-distortion temperature of the blend is comparable to that of pure PC. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

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]

Abstract: The effect of functionalized multiwalled carbon nanotubes (FMWCNTs) on the phase morphology of immiscible high density polyethylene/polyamide 6 (HDPE/PA6, 50/50) blend has been investigated. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to study both the morphology variation of the nanocomposites and the selective distribution of FMWCNTs in the nanocomposites. It is clear that adding small amount of FMWCNTs (<2.0wt.%) does not exert profound influence on the sea-island morphology of the nanocomposites. However, at moderate content of FMWCNTs (2.0 and 5.0wt.%), a typical cocontinuous morphology is detected. Further increasing FMWCNTs content (10.0wt.%) induces phase inversion. The crystallization behaviors of both HDPE and PA6 components were investigated by using differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). The results show the apparent nucleation effect of FMWCNTs for PA6 crystallization due to the selective distribution of FMWCNTs in PA6 phase. Rheological measurements exhibit the presence of FMWCNTs network structure in the nanocomposites. It is suggested that the formation of the cocontinuous morphology and the novel crystallization behaviors of PA6 at high content of FMWCNTs are ascribed to the formation of the FMWCNTs network structure. [Copyright &y& Elsevier]