High density arrays of chromium (Cr) and layered gold/chromium (Au/Cr) nanodots and nanoholes in metal films were fabricated by evaporation onto nanoporous templates produced by the self-assembly of poly(styrene-b-methyl methacrylate) (P(S-b-MMA)) diblock copolymers. The cylindrical microdomains of the asymmetric block copolymer were oriented normal to the surface by balancing interfacial interactions of the blocks with the substrate. By selectively removing either the minor or major component, nanoporous films of PS or nanoscopic posts of PS could be produced. Thus, a template, comprising an array of hexagonally packed pores in a PS matrix or PS posts, was easily fabricated. Evaporation of Cr and Au onto the template, followed by sonication and UV degradation of the PS, left Cr or Au/Cr nanodots or a nanoporous metallic film.

(200 mL) was stirred at 65 C for 72 h. On cooling, the mixture was added to water (300 mL) and the crude product collected by filtration. Repeated reprecipitations from methanol gave 13.15 g (95 % yield) of fluorescent yellow polymer (PIM-1); found C 74. 85, H 4.23, N 6.04 %, C 29 Nitrogen adsorption/desorption measurements were undertaken using a Coulter SA3100 instrument (with foreline filter to avoid contamination with oil vapor) and a Micromeritics ASAP 2020 instrument. Prior to analysis, samples were outgassed for 12±16 h at 120± 150 C.To form a membrane, PIM-1 (0.5 g) was dissolved in THF (25 mL) with stirring. The polymer solution was poured into a flat-bottomed glass petri dish (12 cm diameter) and the solvent allowed to evaporate under a slow flow of nitrogen over a period of about 4 days, then further dried in a vacuum oven at 70 C for 18 h, giving a fluorescent yellow membrane of thickness 40 lm with an apparent surface area (N 2 adsorption, BET analysis) of 620 m 2 g ±1 . Dynamic mechanical thermal analysis (DMTA) of a PIM-1 membrane (dimensions: 22.195 mm 6.2 mm 0.05 mm) was carried out using a Rheometric Scientific RSAIII instrument (frequency: 1 Hz; ramp: 30±450 C at 2 C min ±1 ; strain: 0.1). X-ray diffraction of a PIM-1 film cast onto a glass slide from THF was carried out using a Philips PW 1730 generator (Cu Ka) and Philips PW 1050 goniometer.Pervaporation of phenol/water mixtures was carried out using a batch pervaporation cell with 400 cm 3 feed solution and an effective membrane area of 33.2 cm 2 . The cell temperature was maintained with a thermocouple linked to an electronic temperature control system, constructed by the Department of Chemistry Electronics Workshop. Vacuum (0.1 mbar) on the permeate side was maintained with an Edwards E2M18 vacuum pump and permeate was condensed and frozen within a cold trap cooled with liquid nitrogen. Phenol concentrations were determined by UV spectroscopy (wavelength = 270 nm) using a Hewlett Packard 8452A diode array spectrophotometer. Preparation of Gold Nanowires and Nanosheets in Bulk Block Copolymer Phases under Mild Conditions** By Jong-Uk Kim, Sang-Ho Cha, Kyusoon Shin, Jae Young Jho, and Jong-Chan Lee* ReceivedRecently great efforts have been made to synthesize one-dimensional (1D) [1] and two-dimensional (2D) [2] metal nanostructures because of their unique optoelectronic, magnetic, and mechanical properties, and potential applications in mesoscopic research and nanodevices.[3±5] Among several synthetic approaches for the preparation of the 1D and 2D metal nanostructures, two approaches have been widely used. One is the template-directed methods using various templates, such as mesoporous inorganic materials, [6] organic surfactants, [7] or polymers; [8] the template-directed methods have been most widely used to control the shapes of the metal nanostructures. The other is the crystal growth method controlled by appropriate capping reagents such as polymeric or small molecules, where certain interactions between the molecules and the face...

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IPMC (ionic polymer metal composite), a kind of ionic electroactive polymer (EAP), has been used for various applications because it has light weight and can make large bending deformation under low driving voltage. In the present work, thick IPMC films were fabricated by hot-pressing several thin IPMC films and the actuating performance was evaluated. Displacement and maximum load with applied voltage were measured using a displacement measuring system, a load cell and a multimeter. Several cycles of Pt electroless-plating were performed on the IPMC films to improve the actuating performance. Then, SEM (scanning electron microscopy) micrographs and EDS (energy dispersive spectrometer) profiles of the IPMC specimen were examined. To demonstrate the feasibility of IPMC films for medical or robotic applications, the developed IPMC actuators were applied to artificial fingers and tested.