In view of producing environmentally friendly materials without compromising the properties, new composites containing polylactic acid as matrix and chitosan, with or without keratin fibers have been obtained. The morphological, mechanical, rheological, and thermal characterizations of the composites were performed before and after accelerating weathering. In normal conditions, the presence of keratin improved the toughness and thermal stability of polylactic acid (PLA)/ chitosan material. Upon accelerated weathering, thermal degradation of the PLA matrix was faster in the presence of chitosan, as compared to the composite containing chitosan and keratin. Fractured surfaces of the exposed composites are rougher related to the unexposed samples, as revealed by SEM. XRD analysis recorded selective degradation of the amorphous part of the materials. The decrease of the complex viscosity values after UV exposure of the blends indicated that chain scission was the most prominent phenomenon in accelerated weathering tests.

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In this study, property changes of controlled aged LDPE/feather composites in comparison to those of nonaged samples were investigated by mechanical tests, dynamic rheological and thermal tests, infrared spectroscopy, and oxygen permeability analysis. The viscoelastic behavior of the aged composites was modified, whereas a pseudoplastic character was observed for the nonaged samples. After weathering, infrared spectroscopy indicated the formation of carbonyl and vinyl groups, and the oxygen permeability became significantly higher than for the reference samples. DSC results showed α-helix denaturation of keratin after aging and an increase in crystallinity due to reinforcement of composites containing feather fibers upon UV exposure. An aging time of 500 h was found to induce surface degradation of composites, especially for a feather fiber loading of 10 wt %.

The aim of this work was to obtain an inclusion complex between HP-β-CD and amiodarone in order to increase the solubility of this active agent. Drug−cyclodextrin interactions in solution were investigated using phase solubility studies. The Fourier transform infrared spectroscopy (FT-IR) spectra revealed the presence of the interactions between the components of the inclusion complex. Changes in crystallinity of the drug inside the inclusion complex were confirmed by X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). Thermogravimetric (TG) results demonstrated the modification of the drug thermal behavior due to the interactions with the host cyclodextrin. The dissolution rate of amiodarone from the inclusion complex was considerably increased as compared to dissolution of the pure drug. It has been established that the complexation of amiodarone with HP-β-CD offers the possibility to increase its aqueous solubility without the modification of its original structure.

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