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The new Schiff base, 2,2'-((1Z,1'Z)-(((propane-1,3-diylbis(oxy))bis(2,1-phenyle­ne))bis­(me­tha­­nyl­­ylidene))bis(azanylylidene))diethanol, was investigated as a cor­ro­sion inhibitor of aluminium in 1 M HCl. Polarization and electrochemical impedance mea­surements were used for this purpose. Polarization curves showed that the compound is a mixed-type corrosion inhibitor. Also, the results showed an increase in inhibition efficiency as the concentration of the compound increased. The maximum corrosion inhibition effici­ency of approximately 81 % was reached at the concentration of 2 mg/L of the inhibitor. The results of the density functional theory method were consistent with the experimental results. The surface morphology of the samples was examined under atomic force microscopy.

In this research, nanocomposite films based on starch were developed with the addition of hydroxyapatite nanoparticles as a mineral filler. Hydroxyapatite was synthesized by a chemical method using calcium nitrate and diammonium hydrogen phosphate. Various concentrations of hydroxyapatite nanoparticles were mixed with starch, and the developed films were evaluated in terms of physical, mechanical, and morphological properties. The highest values of mechanical parameters (tensile strength and elongation at break) were determined for the starch/hydroxyapatite film at 15 wt.% hydroxyapatite nanoparticles concentration (3.03 MPa, 37.41%, respectively). As hydroxyapatite concentration was increased from 0 to 20 wt.%, the solubility in water of the films decreased, whereas the solubility in acid increased. The crystalline structure of hydroxyapatite decreased the transparency of film and increased transparency value. Thus, a biodegradable film could be obtained with the addition of hydroxyapatite as a reinforcement filler up to 15 wt.%. It could be developed as a sustainable alternative for packaging industry.

Ternary polymer blends based on polypropylene (PP)/poly(styrene‐ethylene‐butylene‐styrene) (SEBS)/polycarbonate (PC) compatibilized through maleic anhydride‐grafted SEBS were prepared using a twin‐screw extruder. Four different compositions in which the weight ratio of SEBS constituent was varied from 5% up to 30% were formulated in order to assess the relation between morphology and mechanical properties and SEBS/SEBS‐g‐MA weight ratio was set to be 1. Samples were characterized using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and mechanical properties measurements. Microscopic observation confirmed the formation of core‐shell droplets dispersed in the PP matrix in which the rubbery phase encapsulated PC droplets. Individual fibril‐like PC rods were also observed beside the encapsulations. Accordingly, impact resistance progressively improved (28.57‐fold at 30 wt% of SEBS) compared to neat PP while only 6.8% decrease was detected in the yield strength of this sample. SEM micrographs also showed that the population and size of the individual PC particles are higher in the samples containing 5 and 10 wt% of SEBS compared to those containing 20 and 30 wt%, which endow the former with higher chance of heterogeneous nucleation and correspondingly higher crystallization temperature confirmed by DSC results. Introduction of SEBS rubber phase intensified the elastic behavior of the blends supported by DMTA thermograms.

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