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Innovative melt processing technology is necessary for the production of biodegradable polylactide/graphene nanocomposites. In this paper, we present the aqueous spray coating method to prepare graphene-coated polylactide granules for improving the distribution of small graphene contents in polymer matrix during the melt mixing process. Three types of functionalized graphene nanosheets, including graphene oxide (GO), reduced graphene oxide (RGO) and poly(ethylene glycol)/RGO (PEG/RGO), were investigated in the formations of graphene coatings on polylactide granules and subsequent melt-processed nanocomposites. It is found that RGO nanosheets have good interfacial compatibility to form better coatings on polylactide granules. Melt processing of graphene-coated granules produced polylactide/graphene nanocomposites with higher mechanical strengths. Nanocomposite materials containing 0.1% RGO showed the best improvements of mechanical and thermal properties. As-prepared nanomaterials and nanocomposites were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), ultraviolet-visible spectroscopy (UV-Vis), attenuated total reflectance infrared spectroscopy (ATR-FTIR), tensile, flexural and impact measurements, differential scanning calorimetry (DSC) and integrated thermogravimetric analysis (TGA-DTA). In general, the innovative strategy of aqueous spray coating and melt processing is applicable for manufacturing biodegradable PLA/graphene nanocomposites in the sustainable trend of environmentally friendly development. [ABSTRACT FROM AUTHOR]

Starch nanoparticles, synthesized from native starch through the hydrolysis approach, are considered as potential reinforcers to sustainable biodegradable nanocomposite with poly(lactic)acid. Some properties of nanocomposites are upgraded to expand their applications compared to poly(lactic) acid. As relevant, starch nanoparticles are spherically shaped with mainly distributive sizes under 80 nm. Especially, they are homogeneously dispersed in the matrix polymer at high content, resulting in improving the interfaces between matrix polymer and starch nanoparticles, thermal stability, and mechanical properties of nanocomposites. [ABSTRACT FROM AUTHOR]

Abstract: Anatase TiO2 nanotubes grown on Ni foam substrates were successfully synthesized by treating TiO2 nanocrystals coated on an Ni foam in alkaline solution using a facile microwave-assisted hydrothermal method. The as-synthesized TiO2 nanotubes were characterized by SEM, TEM, and XRD. The effects of NaOH concentration, reaction time, hydrothermal temperature, and calcination temperature on the morphology, as well as crystal structure, of the nanotubes were investigated. TiO2 nanotubes synthesized under the optimal conditions were polycrystalline anatases with 4 to 5 multilayers, approximately 10nm wide, and several tens of nanometers long. The possible formation mechanism for TiO2 nanotubes was also discussed in the current paper. [Copyright &y& Elsevier]