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We report on the formation of Laser Induced Periodic Surface Structures in poly (ethylene terephthalate) and poly (ethylene terephthalate)/Expanded Graphite films by laser irradiation with nanosecond pulses at 266 nm. The characterization studies show that the quality of the ripples depends strongly on the irradiation time and fluence and the optimal conditions for obtaining LIPSS are affected by the amount of the expanded graphite present in the film due to the differences in crystallinity, thermal conductivity and thermal diffusivity of the nanocomposites. Physicochemical modifications in the materials were inspected by Raman spectroscopy, the colloidal probe technique and contact angle measurements using different liquids. Results show that there is an increase of the hydrophilicity of the surfaces after laser irradiation together with an increase of the surface free energy and in particular of its polar component. Additionally, the adhesion force estimated by the colloidal probe technique increases after laser nanostructuring.

Design and experiment of polymeric nanocomposites (NCs) for photovoltaic applications with outstanding electrical and thermal properties has been investigated with the introduction of SiC nanofibers (NFs) into the poly(trimethylene terephthalate)-block-poly(tetramethylene oxide) (PTT-PTMO) copolymers. In order to enhance the electrical and thermal conductivity, different concentrations of SiC NFs, ranging from 0.1 to 3.0 wt %, have been selected to mix with PTT-PTMO via in situ polymerization method. This reaction method is an excellent choice for incorporation of high amount of SiC NFs (3 wt %) into the polymer that was confirmed by morphological studies. From dielectric spectroscopy studies a percolating behavior was confirmed at low percolation threshold (less than 2% wt %). Furthermore, the 15% increment for thermal conductivity appeared with combination of 0.5 wt % SiC NFs with PTT-PTMO copolymers, which can be affected by manufacturing process of NCs, state of nanofillers dispersion and aspect ratio of nanofillers.

© 2015 Elsevier Ltd. A synergetic effect between graphene nanoplatelets (GNP) and single-walled carbon nanotubes (SWCNT) leading to an improvement of the electrical conductivity of poly(trimethylene terephthalate-. block-poly(tetramethylene oxide) (PTT-PTMO) based nanocomposites is demonstrated. PTT-PTMO based nanocomposites were prepared with varying concentration of SWCNT and GNP as conducting fillers, and their electrical conductivity and morphology were evaluated using Dielectric and Raman spectroscopies respectively. It has been shown that the addition of SWCNT and GNP enhanced the electrical conductivity of composites, particularly in the case of composites with 0.3 wt. % SWCNT and 0.1 wt. % GNP nanoparticles. These results suggest the existence of synergy arising from the combination of two conducting fillers with different geometrical shapes and aspect ratios as well as different dispersion characteristics in the PTT-PTMO thermoplastic elastomer matrix.