The thermal conductivity of poly(trimethylene terephthalate-block-poly(tetramethylene oxide) copolymer (PTT-PTMO)-based nanocomposites filled with the hybrid system of nanofillers, including single-walled carbon nanotubes (SWCNT) and graphene nanoplatelets (GNP) is studied. At the same loading, SWCNT provided greater thermal conductivity enhancement when added to thermoplastic elastomer matrix when compared to GNP. Moreover, SEM images showed that SWCNT and GNP were well dispersed in PTT-PTMO, suggesting that in situ polymerization is a highly efficient method for preparing hybrid nanocomposites with low loading of carbon nanofillers. To further improve thermal conductivity of PTT-PTMO-based nanocomposites, a hybrid SWCNT/GNP was used. When the ratio of SWCNT to GNP was 5:1, i.e. 0.5 wt% of SWCNT and 0.1 wt% of GNP, the PTT-PTMO-based nanocomposites exhibited the highest thermal conductivity of 0.30 W/m·K, higher than that filled with SWCNT and GNP alone. This suggests that the combination of two types of nanofillers, which differ in shape, allows obtaining the synergistic effect for the thermal conductivity enhancement of PTT-PTMO. C 2015 Wiley Periodicals, Inc. Adv Polym Technol 201 , , 21611; View this article online at wileyonlinelibrary.com.

The physical properties of magnetorheological elastomers (MRE) are a complex issue and can be influenced and controlled in many ways, e.g. by applying a magnetic field, by external mechanical stimuli, or by an electric potential. In general, the response of MRE materials to these stimuli is crucially dependent on the distribution of the magnetic particles inside the elastomer. Specific knowledge of the interactions between particles or particle clusters is of high relevance for understanding the macroscopic rheological properties and provides an important input for theoretical calculations. In order to gain a better insight into the correlation between the macroscopic effects and microstructure and to generate a database for theoretical analysis, x-ray micro-computed tomography (X-μCT) investigations as a base for a statistical analysis of the particle configurations were carried out. Different MREs with quantities of 2-15 wt% (0.27-2.3 vol%) of iron powder and different allocations of the particles inside the matrix were prepared. The X-μCT results were edited by an image processing software regarding the geometrical properties of the particles with and without the influence of an external magnetic field. Pair correlation functions for the positions of the particles inside the elastomer were calculated to statistically characterize the distributions of the particles in the samples.

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A recent discovery of the unique biological properties of two-dimensional transition metal carbides (MXenes) resulted in intensive research on their application in various biotechnological areas, including polymeric nanocomposite systems. However, the true potential of MXene as an additive to bioactive natural porous composite structures has yet to be fully explored. Here, we report that the addition of 2D Ti3C2Tx MXene by reducing the porosity of the chitosan-hyaluronate matrix nanocomposite structures, stabilized by vitamin C, maintains their desired antibacterial properties. This was confirmed by micro computed tomography (micro-CT) visualization which enables insight into the porous structure of nanocomposites. It was also found that given large porosity of the nanocomposite a small amount of MXene (1–5 wt.%) was effective against gram-negative Escherichia coli, gram-positive Staphylococcus aureus, and Bacillus sp. bacteria in a hydrogel system. Such an approach unequivocally advances the future design approaches of modern wound healing dressing materials with the addition of MXenes.

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)-blockpoly(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 2 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.