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As a packaging materials candidate, based on a polylactic acid/ polybutylene adipate terephthalate (PLA/PBAT) blends (90/10 and 75/25 wt/wt) containing 1, 3, and 5 phr hydrophilic (HPL) and hydrophobic (HPB) nanosilica (NS) particles in the presence of a multifunctional epoxide compatibilizer were prepared by melt mixing, in a twin-screw extruder. Scanning electron microscopic studies confirmed a matrixdroplet morphology with finer dispersed domains at higher NS content. Energy dispersive spectroscopy mapping also indicated uniform dispersion of NS in blends, with some agglomerates at higher content of nanoparticles. Moreover, transmission electron microscope was applied to study the impact of nanofillers' localization on the systems' morphology. It was observed that NS particles localized at the PLA-PBAT interface. In addition, thermogravimetric analysis (TGA) was used to investigate thermal stability and thermal degradation kinetics. Data indicates that hydrophobic NS improved thermal stability. The activation energy of degradation was calculated using several techniques of data modeling, including Friedman, Flynn-Ozawa-Wall, and Kissinger-Akahira-Sunose models. Among blend nanocomposites, 75/25 blend containing 5 phr HPB NS had the maximum degradation activation energy, suggesting that this sample had the most resistance to heat degradation. The intensity of the TGA/FTIR peaks of the evolved products was found to be correlated with the activation energy. The Criado's technique was also used to investigate the changes in the thermal degradation mechanism. [ABSTRACT FROM AUTHOR]

The nanocomposite blends of ultra-high-molecular-weight polyethylene (UHMWPE) and high-density PE (HDPE) reinforced with 1 wt% of multi-wall carbon nanotube (MWCNT) were prepared by melt mixing at different compositions in an internal mixer. Two different grades of HDPE were used in this research to improve the processability of UHMWPE. Rheological, thermal, morphological, and mechanical properties were investigated for both (UHMWPE/HDPE) blends and their nanocomposites. The results confirmed the reduction in melt viscosity and improvement in the processability of UHMWPE by the addition of HDPE. Differential scanning calorimetry (DSC) results showed a single melting and crystallization peak, and the broadness of these peaks in blends compared to pure components indicated that two components form separate crystals. The effect of incorporating MWCNT to the blend samples on mechanical properties was studied, and the samples prepared with HDPE 5218 exhibited slight improvement in mechanical properties. Incorporating MWCNT into the blend of UHMWPE (20 wt%) accelerated crystallization; but in higher contents of UHMWPE, crystallization of the composites was slightly delayed. Rheological data exhibited lower complex viscosity and storage modulus and therefore lower elasticity for UHMWPE/HDPE/MWCNT nanocomposites compared to their blends. Drop in viscosity and storage modulus as well as tensile strength of nanocomposites compared to their blends was attributed to adsorption of higher molar mass polyethylene chains onto MWCNT surface. The morphology of nanocomposites was analyzed by scanning electron microscopy (SEM) and phase separation, and probably localization of MWCNT predominantly into HDPE matrix and HDPE/UHMWPE interface was concluded. X-ray diffraction (XRD) patterns indicated that MWCNT was well distributed and dispersed in HDPE matrix. [ABSTRACT FROM AUTHOR]