Conventional polyurethanes (PUs) are among biomaterials not intended to degrade but are susceptible to hydrolytic, oxidative and enzymatic degradation in vivo. Biodegradable PUs are typically prepared from polyester polyols, aliphatic diisocyanates and chain extenders. In this work we have developed a degradable monomer based on α-amino acid to accelerate hard segment degradation. Thus a new class of degradable poly(ether-urethane-urea)s (PEUUs) was synthesized via direct reaction of 4,4'-methylene-bis(4-phenylisocyanate) (MDI), L-leucine anhydride (LA) and polyethylene glycol with molecular weight of 1,000 (PEG-1000) as polyether soft segment. The resulting polymers are environmentally biodegradable and thermally stable. Decomposition temperatures for 5 % weight loss occurred above 300 °C by TGA in nitrogen atmospheres. Some structural characterization and physical properties of these polymers before and after degradation in soil, river water and sludge are reported. The environmental degradation of the polymer films was investigated by SEM, FTIR, TGA, DSC, GPC and XRD techniques. A significant rate of degradation occurred in PEUU samples under river water and sludge condition. The polymeric films were not toxic to E. coli (Gram negative), Staphylococcus aureus and Micrococcus (Gram positive) bacteria and showed good biofilm formation on polymer surface. Our results show that hard segment degraded selectively as much as soft segment and these polymers are susceptible to degradation in soil and water. Thus our study shows that new environment-friendly polyurethane, which can degrade in soil, river water and sludge, is synthesized.

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Novel generation rechargeable battery technology awaits advanced materials with stable structures and special construction in order to have control over side reactions and provide a well-balanced set of physicochemical interactions to store electrochemical energy. Here, we synthesize various morphology and size of AlV 3 O 9 structures (AV) via a simple hydrothermal method. The high specific capacity for flower-like, rod-like and polygon spheres are 233, 317 and 278.5 mAh g −1 respectively. Also, urchin-like AlV 3 O 9 as optimum electrode deliveries discharge capacities 294.65 mAh g −1 (as cathode) and 609.09 mAh g −1 (as anode) at the current rate of 0.1 C, which leads to capacity maintenance of 99.79% after 100 round cycles at a 1 C current rate with excellent rate capacity. We opine that the framework of this research arranges a principle of fabrication for electrochemically appropriate constructions, which is of excellent potential and function for progressing battery storage efficiency by modifying the structure and morphology of AlV 3 O 9 materials on multidimensional structures.

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