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Multiwalled carbon nanotube (MWNT)/poly (vinyl alcohol) (PVA) blend membranes were prepared by the solution-casting method to determine the effect of MWNTs with nanoscale empty inner space along the tube length on the pervaporation performance of a PVA membrane in the separation of alcohol/water mixtures. The blend membranes were then characterized with several analytical methods such as transmission electron microscopy, differential scanning calorimetry, and X-ray diffractometry: Transmission electron microscopy showed that the MWNTs were homogeneously distributed through the PVA matrix. The glass-transition temperature of the PVA membrane was increased from 69.21 to 78.53 C via blending with MWNTs. The crystallinity of the PVA matrix decreased with increasing MWNTs up to 5 wt % from 41 to 36%. The pervaporation properties of the blend membranes were completely different from those of the pure PVA membrane in the separation of water/ethanol mixtures. The flux of the membrane was increased with the amount of MWNTs, whereas the separation factor was maintained up to 1.0 wt % MWNTs. However, beyond that, it was reduced. These results suggested that two factors, the crystallinity of the membrane and the diameters of the MWNTs, affected the performance of the membranes.

Summary: The effect of multi-walled carbon nanotubes (MWNTs) incorporated for the modification of membrane performances was studied. Two different types of membranes were prepared by using MWNTs: one was polysulfone (PSf) ultrafiltration (UF) membrane and the other was polyvinyl alcohol (PVA) pervaporation membrane. The PSf UF membranes with different contents of MWNTs were prepared by the conventional phase inversion process, and used for water-treatment. On the other hand, the PVA membranes with different amount of MWNTs were prepared by the casting and drying method, and used for the pervaporation separation of water out of ethanol solution containing 10% of water. The two different types of membranes were then characterized with several analytical methods to figure out how the MWNTs were distributed through the membranes and affect on the properties of them: For the PSf membranes, the MWNTs mainly located on the surface of the membranes made them more hydrophilic and improved the selective permeation performances of the membranes. In the case of the PVA membranes, the MWNTs were distributed rather homogeneously through out the membranes, and affected on the micro-morphology of the membranes, causing them to have different pervaporation performances.

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Silicone elastomer actuators were investigated to develop a simple and industrially scalable product with improved mechanical properties, such as a low modulus, high tearing strength, and good resilience, and enhanced electromechanical actuation properties. Silicone elastomers were fabricated via a hydrosilylation addition reaction with a vinyl-end-functionalized poly(dimethyl siloxane) (V), a multivinyl-functionalized silicone resin, and a crosslinker in the presence of a platinum catalyst. For the larger electromechanical actuation response, the silicone dielectric elastomer actuator had to have a larger molecular weight of poly(dimethyl siloxane), a smaller hardener content, and a resin-free composition. However, the silicone elastomer actuators needed to include a small amount of resin to improve the tearing strength. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40030.