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In order to address the challenges associated with antibiotic resistance by bacteria, two new complexes, Ni(II) and Zn(II), have been synthesized using the conventional method based on Schiff base ligand (E)-2-((5-bromothiazol-2-yl) imino) methyl) phenol. The Schiff base ligand (HL) was synthesized using salicylaldehyde and 5-(4-bromophenyl)thiazol-2-amine in both traditional and efficient, ecologically friendly, microwave-assisted procedures. The ligand and its complexes were evaluated by elemental analyses, FTIR spectroscopy, UV-Vis spectroscopy, nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA) and magnetic susceptibility. The ligand and its complexes were tested for antibacterial activity against three Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Methicillin-resistant Staphylococcus aureus ATCC 43300 and Enterococcus faecalis ATCC 29212) and three Gram-negative bacteria (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and Klebsiella pneumoniae ATCC 700603). The findings demonstrate the potent activity of the ligand and its complexes against selective bacteria but the Ni(II) complex with MIC values ranging from 1.95 to 7.81 µg/mL outperformed all other compounds, including the widely used antibiotic Streptomycin. Furthermore, the docking study provided evidence supporting the validity of the antimicrobial results, since the Ni complex showed superior binding affinity against to E. coli NAD synthetase, which had a docking score (−7.61 kcal/mol).

A series of poly(ethylene-co-vinyl alcohol)/poly(ε-caprolactone) blends with different compositions were prepared using solvent casting. The miscibility of this pair of polymers was investigated using differential scanning calorimetry (DSC), and proved by a negative Flory interaction parameter value calculated from the Nishi–Wang equation. The miscibility of this blend was also confirmed by scanning electronic microscopy (SEM). The thermal behaviors of the obtained materials were investigated by DSC, thermogravimetric analysis, and direct analysis in real-time–time-of-flight mass spectrometry and the results obtained were very relevant. Furthermore, the crystalline properties of the obtained materials were studied by DSC and X-ray diffraction where the Ozawa approach was adopted to investigate the non-isothermal crystallization kinetics. The results obtained revealed that this approach described the crystallization process well.