Differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and dynamic mechanical analysis (DMA) properties of poly(lactic acid)/ poly(butylene adipate-co-terephthalate) (PLA/PBAT) specimens suggest that only small amounts of poor PLA and/ or PBAT crystals are present in their corresponding melt crystallized specimens. In fact, the percentage crystallinity, peak melting temperature and onset re-crystallization temperature values of PLA/PBAT specimens reduce gradually as their PBAT contents increase. However, the glass transition temperatures of PLA molecules found by DSC and DMA analysis reduce to the minimum value as the PBAT contents of PLA x PBAT y specimens reach 2.5 wt %. Further morphological and DMA analysis of PLA/PBAT specimens reveal that PBAT molecules are miscible with PLA molecules at PBAT contents equal to or less than 2.5 wt %, since no distinguished phase-separated PBAT droplets and tan d transitions were found on fracture surfaces and tan d curves of PLA/PBAT specimens, respectively. In contrast to PLA, the PBAT specimen exhibits highly deformable properties. After blending proper amounts of PBAT in PLA, the inherent brittle deformation behavior of PLA was successfully improved. Possible reasons accounting for these interesting crystallization, compatible and tensile properties of PLA/PBAT specimens are proposed.

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Systematically investigations of the plasticizing effects of triacetine (TAc) on crystallization, chain mobility, microstructure, and tensile properties of the Poly (lactic acid)/triacetine (PLA/TAc) blends are reported. A new transition hump was observed on the tan d curve of PLA x TAc y specimens at temperatures ranging from À80 to À20 C. Thermal, wide angle X-ray diffraction (WAXD) and dynamic mechanical analysis properties of PLA and PLA x TAc y series specimens suggest that PLA and PLA xTAc y series specimens can hardly crystallize by cooling the melt in room temperature. However, significant recrystallization of a form PLA crystals was found during the annealing processes of PLA x TAc y series specimens. Some ''less perfect'' b form PLA crystals were found as the TAc contents of PLA x TAc y specimens reach 30 wt %. Further morphological analysis show that the inherent brittle deformation behavior of the PLA specimen was successfully transformed into relatively ductile fracture behavior after blending sufficient but optimum amounts of TAc in PLA resins. Possible reasons accounting for this interesting recrystallization, thermal, microstructure and tensile properties of PLA x TAc y specimens are proposed.

The Fourier transform infrared results suggest that the carboxylic acid groups of poly(lactic acid) (PLA) molecules react with the epoxy groups of molecules of Ethylene Glycidyl Methacrylate Copolymer (EGMC) during the reactive extrusion processes of PLA x EGMC y specimens. The tensile and tear strength values of PLA x-EGMC y blown-film specimens in machine and transverse directions improve significantly, and reach their maximal values as their EGMC contents approach an optimum value of 6 wt.%. The melt shear viscosity values of PLA x EGMC y resins, measured at varying shear rates, are significantly higher than those of the PLA resin, and increase consistently with their EGMC contents. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) of PLA and PLA x EGMC y specimens reveal that the percentage crystallinity, peak melting temperature, and onset recrystallization temperature values of PLA x EGMC y specimens reduce gradually as their EGMC contents increase. In contrast, the glass transition temperatures of PLA x-EGMC y specimens increase gradually in conjunction with their EGMC contents. Demarcated porous morphology with several connected fungi-decomposed cavities was found on the surfaces of the PLA x EGMC y specimens after being buried for specific amounts of time, in which the sizes of the fungi-decomposed cavities found on the surfaces of buried PLA x EGMC y specimens reduce significantly as their EGMC contents increase. Further DMA and morphological analysis of PLA x EGMC y specimens reveal that the EGMC molecules are compatible with PLA molecules at EGMC contents equal to or less than 2 wt.% because no phaseseparated EGMC droplets and tan δ transitions were found on fracture surfaces and tan δ curves of PLA x-EGMC y specimens, respectively. The possible reasons for these remarkable properties of the PLA/EGMC specimens are proposed in this study.

In this study, different fractions of fly ashes, poly (tetramethylene glycol) (PTMG), and excess 4, 4Ј-diphenylmethane diisocyanate (MDI) were added into a reactor to form the polyurethane (PU)/fly ashes blend. It is evident that heavy metals can be encapsulated in PU foam, which was shown by the results of a toxicity characteristic leaching procedure (TCLP) test. After the tensile strength test, the elongation test, and the hardness test, the physical and chemical properties of the PU/fly ashes blend were acceptable for commercial applications. Meanwhile, based on the leaching criteria of Environmental Protection Administration (EPA) of Taiwan, comparing the new PU/fly ashes blended with 18% fly ashes and PU/fly ashes blended in ambience at room temperature for 1 year's time revealed both blends to function effectively in the tests. The results from the weatherability test illustrate that the maximum percentage of fly ashes allowed in the blends was 18%. Therefore, fly ashes blended with PU foam was a new and effective recycle method to deal with MSW. We aim to evaluate the processing parameters to create a new application option of the fly ashes so that the treatment loading of residual can be reduced.