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Available online March 22, 2013.- El pdf del artículo es la versión post-print.-Supplementary data associated with this article can be found on pages 21-23. ; We here present an effective strategy to prepare enhanced composites using poly(vinyl alcohol) (PVA) and multiwalled carbon nanotubes (MWCNT). It contains two essential steps. First, the elaboration of homogeneous aqueous MWCNT dispersions and the selection of the most effective dispersing agent. In a sequential dispersion protocol for seven common dispersants, including surfactants and polymers, the dispersion quality and dispersion ability, independent of the intrinsic nature of the dispersing agent were established using zeta-potential and UV-Vis-spectroscopy. Second, the combination of the most effective dispersing agent, namely dodecylbenzenesulfonate (SDBS) with a polymer dispersant of high affinity towards the PVA matrix, namely polyvinylpyrrolidone (PVP). This resulted in homogeneous PVA-MWCNT composites with significantly improved glass transition temperature by up to 12 ºC as a function of the sequential order of dispersant addition. The presented dispersion strategy is straightforward and thus may provide a fast, reliable and general guide for fabricating nanotube composites with improved performance. ; This research was supported by Spanish Ministry of Science and Innovation (MICINN) under project MAT2010-15026, CSIC under project 201080E124, and the Government of Aragon (DGA) under project DGA-T66 CNN. The authors thank Nanocyl S.A. (Sambreville, Belgium) for providing nanotube samples. ; Peer reviewed

Polyhydroxyalkanoates (PHAs) are nowadays considered competent candidates to replace traditional plastics in several market sectors. However, commercial PHA materials exhibit unsatisfactory smells that can negatively affect the quality of the final product. The cause of this typical rancid odour is attributed to oxidized cell membrane glycolipids, coming from Gram-negative production strains, which remain frequently attached to PHAs granules after the extraction stage. The aim of this research is the development of customised PHA bio-nano-composites for industrial applications containing organomodified nanoclays with high adsorbance properties able to capture volatile compounds responsible for the displeasing fragrance. To this end, a methodology for the detection and identification of the key volatiles released due to oxidative degradation of PHAs has been established using a headspace solid-phase microextraction technique. We report the development of nine bio-nano-composite materials based on three types of commercial PHA matrices loaded with three species of nanoclays which represent a different polar behaviour. It has been demonstrated that although the reached outcoming effect depends on the volatile nature, natural sepiolite might result in the most versatile candidate for any the PHA matrices selected. ; The authors gratefully acknowledge the Government of Aragón (DGA) under the project T08_17R (I+AITIIP) for support and financial aid for this publication.

Available online June 23, 2012.- El pdf del artículo es la versión post-print ; Composites of thermoplastic polyurethane (TPU) and ultra-thin graphite (UTG) with concentrations ranging from 0.5 wt.% to 3 wt.% were prepared using a solution compounding strategy. Substantial reinforcing effects with increased loadings are achieved. Compared to neat TPU, values for storage modulus and shear viscosity are enhanced by 300% and 150%, respectively, for UTG concentrations of 3 wt.%. Additionally, an enhancement of thermal properties is accomplished. The crystallization temperature and thermal stability increased by 30 C and 10 C, respectively, compared to neat TPU. Furthermore, the use of oxidized UTG (UTGO) with its added functional oxygen groups suggests the presence of chemical interactions between UTG and TPU, which additionally impact on the thermal properties of the corresponding composites. Controlling the oxidation degree, thus offers further possibilities to obtain composites with tailored properties. The presented approach is straightforward, leads to homogeneous TPU-UTG composites with improved materials properties and is especially suitable for commercial UTG materials and further up-scaled production. ; This research was supported by IMPIVA under project (IMIDIP/2010/58), Spanish Ministry of Science and Innovation (MICINN) under project MAT2010-15026, CSIC under project 201080E124, and the Government of Aragon (DGA) and the European Social Fund (ESF) under project DGA-ESF-T66 CNN. M. C. thanks MICINN and ESF for her grant nº BES-2008-003503. Authors thank Merquinsa S.L. (Barcelona, Spain) and AVANZARE S.L. (La Rioja, Spain) for kindly providing polyurethane and ultrathin graphite samples, respectively. ; Peer Reviewed

[EN] Composites of thermoplastic polyurethane (TPU) and ultra-thin graphite (UTG) with concentrations ranging from 0.5 wt.% to 3 wt.% were prepared using a solution compounding strategy. Substantial reinforcing effects with increased loadings are achieved. Compared to neat TPU, values for storage modulus and shear viscosity are enhanced by 300% and 150%, respectively, for UTG concentrations of 3 wt.%. Additionally, an enhancement of thermal properties is accomplished. The crystallization temperature and thermal stability increased by 30 C and 10 C, respectively, compared to neat TPU. Furthermore, the use of oxidized UTG (UTGO) with its added functional oxygen groups suggests the presence of chemical interactions between UTG and TPU, which additionally impact on the thermal properties of the corresponding composites. Controlling the oxidation degree, thus offers further possibilities to obtain composites with tailored properties. The presented approach is straightforward, leads to homogeneous TPU-UTG composites with improved materials properties and is especially suitable for commercial UTG materials and further up-scaled production. ; This research was supported by IMPIVA under Project (IMIDIP/2010/58), Spanish Ministry of Science and Innovation (MICINN) under Project MAT2010-15026, CSIC under Project 201080E124, and the Government of Aragon (DGA) and the European Social Fund (ESF) under Project DGA-ESF-T66 CNN. M.C. thanks MICINN and ESF for her Grant No. BES-2008-003503. Authors thank Merquinsa S.L. (Barcelona, Spain) and Avanzare S.L. (La Rioja, Spain) for kindly providing polyurethane and ultra-thin graphite samples, respectively. ; Menes, O.; Cano, M.; Benedito, A.; Giménez Torres, E.; Castell, P.; Maser, WK.; Benito, AM. (2012). The effect of ultra-thin graphite on the morphology and physical properties of thermoplastic polyurethane elastomer composites. Composites Science and Technology. 72(13):1595-1601. https://doi.org/10.1016/j.compscitech.2012.06.016 ; S ; 1595 ; 1601 ; 72 ; 13

9 pages, 9 figures.-- Available online 21 February 2014 ; The effect of -irradiation on the structure and composition of chemically synthesized few-layered graphene materials was studied. Fully oxidized graphene oxide and graphene nanoribbons, as well as their respective chemically post-reduced forms, were treated under -irradiation in an air-sealed environment. Three different irradiation doses of 60, 90 and 150 kGy were applied. Structure and composition of the irradiated materials were analyzed by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Raman spectroscopy and Xray photoelectron spectroscopy (XPS). The XRD patterns were not affected by - irradiation, and small changes were observed in the FTIR and TGA results. However, significant modifications were detected by Raman spectroscopy and XPS, particularly in the Raman G/D band intensity ratios and in the C 1s XPS profiles. Comparatively, the changes in Raman and XPS spectra after -irradiation were even greater than those occurring during the chemical reduction of graphene oxides. Our results indicate that the graphene carbon lattice was strongly affected by -irradiation, but the materials experienced small variations in their oxygen content. ; This work was funded by the Spanish MINECO under the projects TEC2010-15736, MAT2010-15026, MAT2010-16175 (CICYT) and PRI-PIBAR-2011-1, CSIC under Project 201080E124 and the Government of Aragon (DGA) and the European Social Fund (ESF) under Project DGA-ESF-T66 CNN. ; Peer reviewed