The control of crystallization is important at all processing stages of the PET bottle industry, from the manufacture of bottle resins to the fabrication of preforms and bottles. In this work, we sought to evaluate critically three methods of crystallinity measurement. We have used density, Differential Scanning Calorimetry (DSC), and Modulated Differential Scanrun ' g Calorimetry (MDSC) to study the crystallinity of PET chips, preforms, and bottles. The accuracy, precision, and general validity of each technique and the problems of interpretation are discussed.

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A bionanocomposite based on biosynthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and reinforced with silver@zinc oxide (Ag–ZnO) was synthesized in variable loadings of Ag–ZnO using the in-situ casting dissolution technique. The degradable biopolymer PHBV had been biosynthesized from date waste as a renewable carbon source. The fabricated products were investigated as promising antibacterial materials. The Ag–ZnO nanoparticles were also synthesized using the green method in the presence of Gum Arabic. The Ag–ZnO nanoparticles were loaded within the PHBV biopolymer backbone at concentration of 1%, 3%, 5% and 10%, PHBV/Ag–ZnO(1,3,5,10%). The chemical structure, morphology, physical and thermal properties of the PHBV/Ag–ZnO bionanocomposites were assessed via common characterization tools of FTIR, TGA, XRD, SEM and EDX. One step of the degradation process was observed in the range of 200–220 °C for all the obtained materials. The onset degradation temperature of the bionanocomposites have been noticeably increased with increasing the nanofiller loading percentage. In addition, fabricated products were investigated for their interesting antibacterial performance. A detailed biological screening for the obtained products was confirmed against some selected Gram-positive and Gram-negative strains S. aureus and E. coli, respectively. Overall, the bionanocomposite PHBV/Ag–ZnO(10%) was the most potent against both types of the selected bacteria. The order of bacterial growth inhibition on the surface of the fabricated bionanocomposites was detected as follows: PHBV/Ag–ZnO(10%) > PHBV/Ag–ZnO(5%) > PHBV/Ag–ZnO(3%) > PHBV/Ag–ZnO(1%).

A facile and short synthesis of a series of quinazolino [1,4]benzodiazepine alkaloids, including asperlicin C, circumdatin H and some analogues, is reported utilizing coupling of readily available [1,4]benzodiazepine with 2-nitrobenzoyl chlorides, followed by a reductive Nheterocyclization.