The use of biodegradable polymers is of great importance nowadays in many applications. Some of the most commonly used biopolymers are polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) due to their superior properties and availability. In this manuscript, we use a facile and green modification method of organoclay (OC) by antimicrobial natural rosin which is considered as a toxicity-free reinforcing material, thus keeping the green character of the material. It increases the interlayer spacing between the clay platelets. This was proven by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) and found to impart antimicrobial properties to PLA/PBAT blends. The morphology of the resulting blends was conducted using scanning and transmission electron microscopies (SEM and TEM), and evidence of exfoliation and intercalation was observed. The thermal properties of the blends were studied using differential scanning calorimetry (DSC), and a detailed study of the crystallization of both PLA and PBAT was reported showing cold crystallization behavior of PLA. The final effect on mechanical and antimicrobial properties was also investigated. The obtained results reveal excellent possibility of using expanded OC modified PLA/PBAT polymer blends by adding a green material, antimicrobial natural rosin, for food packaging and biomembranes applications.

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Layer-by-layer (LbL) deposition of polyelectrolytes within nanopores in terms of the pore size and the ionic strength was experimentally studied. Anodic aluminum oxide (AAO) membranes, which have aligned, cylindrical, nonintersecting pores, were used as a model nanoporous system. Furthermore, the AAO membranes were also employed as planar optical waveguides to enable in situ monitoring of the LbL process within the nanopores by optical waveguide spectroscopy (OWS). Structurally well-defined N,N-disubstituted hydrazine phosphorus-containing dendrimers of the fourth generation, with peripherally charged groups and diameters of approximately 7 nm, were used as the model polyelectrolytes. The pore diameter of the AAO was varied between 30-116 nm and the ionic strength was varied over 3 orders of magnitude. The dependence of the deposited layer thickness on ionic strength within the nanopores is found to be significantly stronger than LbL deposition on a planar surface. Furthermore, deposition within the nanopores can become inhibited even if the pore diameter is much larger than the diameter of the G4-polyelectrolyte, or if the screening length is insignificant relative to the dendrimer diameter at high ionic strengths. Our results will aid in the template preparation of polyelectrolyte multilayer nanotubes, and our experimental approach may be useful for investigating theories regarding the partitioning of nano-objects within nanopores where electrostatic interactions are dominant. Furthermore, we show that the enhanced ionic strength dependence of polyelectrolyte transport within the nanopores can be used to selectively deposit a LbL multilayer atop a nanoporous substrate.

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A novel method is presented to synthesize herringbone-stacked carbon nanofibers in high selectivity using cobaltocene as the catalytic precursor. Thiophene was essential for carbon nanofiber growth while hydrogen was used as the carrier gas. Selectivity close to 100% was achieved using cobaltocene, thiophene, and hydrogen reacted at 1100°C. The conversion rate of the nanofibers collected in the cold trap was approximately 1.5 wt % of the initial products. The effect of the catalytic precursor temperature, thiophene, and acetylene was investigated, with reference to nanofiber diameter and selectivity.

Zinc oxide (ZnO) is a very important compound used in several industries. We synthesized ZnO with different particle sizes and it was incorporated in high-density polyethylene (HDPE) matrix. The resulting nanocomposites were characterized using thermal, physical, and morphological techniques. The mechanical properties of the nanocomposites were also assessed. The nanocomposites were studied for their ultraviolet (UV) absorption properties and were shown to have very good spectral as well as mechanical properties which make them a perfect candidate for applications where UV absorption is essential for example food packing, UV shields, and many other applications.

In this work, we present a new strategy to construct redox‐active molecular platforms to be used as molecular rectifiers with tunable and amplifiable electronic readout. The approach is based on using ligand‐receptor biological interactions to bioconjugate electroactive bio‐inorganic building blocks onto metal electrodes. The stability of the self‐assembled interfacial architecture is provided by multivalent macromolecular ligands that act as scaffolds for building‐up the multilayered structures. The ability of these electroactive supramolecular architectures to generate a unidirectional current flow and tune the corresponding electronic readout was demonstrated by mediating and rectifying the electron transfer between redox donors in solution and the Au electrode. The redox centers incorporated into the assembled architecture in a topologically controlled manner are responsible for tuning the amplification of the rectified electronic readout, thus behaving as a tunable bio‐supramolecular diode. Our experimental results obtained with these redox‐active bio‐supramolecular architectures illustrate the versatility of molecular recognition‐directed assembly in combination with hybrid bio‐inorganic building blocks to construct highly functional interfacial architectures.