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The aim of this work is to compare the scavenging performance and oxygen absorption kinetics of active food packaging films, produced by adding the same percentage of two different formulations of polymeric oxygen scavengers, both copolyester based and designed for PET packaging. Rheological analyses were conducted to investigate possible differences among the macromolecular structure, while oxygen absorption measurements in continuous were performed to evaluate the influence of the different composition on the scavenging phenomenon. The results revealed differences in the molecular chains, and an enhanced formulation for one of the scavengers, with increased scavenging power and exhaustion times. [ABSTRACT FROM AUTHOR]

The present work focuses on the possibility of conveniently tuning materials in PLA based nanocomposites in order to improve their processability in manufacturing processes where extensional flow is mainly involved. Nanocomposites at a constant silicate loading were produced by melt compounding, using a commercial polylactide grade (PLA 4032D) and two different organo-silicates (Cloisite 30B and Nanofil SE3010). A morphological characterization in solid and molten state, realized by TEM investigations and shear rheological measurements, firstly pointed out the influence of composition on the nanostructure of the hybrid systems. All the samples were then submitted to uniaxial stretching and the rheological response of the different nanocomposites was correlated to the initial nanostructure and the different polymer-clay affinity. [ABSTRACT FROM AUTHOR]

This work focuses on the possibility of improving performance properties of polylactide films for packaging applications by melt mixing silicate nanoparticles within PLA matrix. Nanocomposites at various silicate loadings were produced by cast-film extrusion using two different temperature profiles. Oxygen barrier and mechanical properties of the produced films were investigated and correlated to their nanostructure through analytical techniques sensitive to different aspect of the same morphology, such as TEM, XRD and rheological analyses. [ABSTRACT FROM AUTHOR]

In this work the protective efficacy and stability against UV weathering of polymeric nanocomposites for concrete (CLS) surface protection have been evaluated. In particular, nanocomposite hybrids were prepared dispersing a commercial organomodified montmorillonite (Cloisite 30B) in two different polymeric matrices, one based on fluoroelastomers (Fluoline CP), the other on silane and siloxane (Antipluviol S). The obtained systems were characterized by several techniques (SAXD, DSC, TGA, FT-IR, contact angle measurements, colorimetry), before and after accelerated aging due to UV exposure, in order to evaluate the effect of the nanoscale dispersion of the organoclay on the properties and the UV stability of the treatments. [ABSTRACT FROM AUTHOR]