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Layer Film (layer + film)
Selected AbstractsHydrothermal Growth: Polymer-Templated Hydrothermal Growth of Vertically Aligned Single-Crystal ZnO Nanorods and Morphological Transformations Using Structural Polarity (Adv. Funct.ADVANCED FUNCTIONAL MATERIALS, Issue 18 2010Mater. Abstract Position-configurable, vertical, single-crystalline ZnO nanorod arrays are fabricated via a polymer-templated hydrothermal growth method at a low temperature of 93 °C. A sol-gel processed dense c -oriented ZnO seed layer film is employed to grow nanorods along the c -axis direction [0001] regardless of any substrate crystal mismatches. Here, one-beam laser-interference lithography is utilized to fabricate nanoscale holes over an entire 2-in. wafer during the preparation of the polymer template. As such, vertically aligned ZnO nanorods can be grown from the seed layer exposed at the bottom of each hole. Furthermore, morphological transformations of the ZnO nanorods into pencil-like, needle-like, tubular, tree-like, and spherical shapes are obtained by controlling the growth conditions and utilizing the structural polarity of the ZnO nanorods. [source] Polymer-Templated Hydrothermal Growth of Vertically Aligned Single-Crystal ZnO Nanorods and Morphological Transformations Using Structural PolarityADVANCED FUNCTIONAL MATERIALS, Issue 18 2010Ki Seok Kim Abstract Position-configurable, vertical, single-crystalline ZnO nanorod arrays are fabricated via a polymer-templated hydrothermal growth method at a low temperature of 93 °C. A sol-gel processed dense c -oriented ZnO seed layer film is employed to grow nanorods along the c -axis direction [0001] regardless of any substrate crystal mismatches. Here, one-beam laser-interference lithography is utilized to fabricate nanoscale holes over an entire 2-in. wafer during the preparation of the polymer template. As such, vertically aligned ZnO nanorods can be grown from the seed layer exposed at the bottom of each hole. Furthermore, morphological transformations of the ZnO nanorods into pencil-like, needle-like, tubular, tree-like, and spherical shapes are obtained by controlling the growth conditions and utilizing the structural polarity of the ZnO nanorods. [source] Preparation, characterization, and electrical properties of dual-emissive Langmuir-Blodgett films of some europium-substituted polyoxometalates and a platinum polyyne polymerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 4 2010Li Liu Abstract A new series of organometallic/inorganic composite Langmuir-Blodgett (LB) films consisting of a rigid-rod polyplatinyne polymer coordinated with 2,7-bis(buta-1,3-diynyl)-9,9-dihexylfluorene (denoted as PtP) as the ,-conjugated organometallic molecule, an europium-substituted polyoxometalate (POM; POM = Na9EuW10O36, K13[Eu(SiW11O39)2] and K5[Eu(SiW11O39)(H2O)2]) as the inorganic component, and an amphiphilic behenic acid (BA) as the auxiliary film-forming agent were prepared. Structural and photophysical characterization of these LB films were achieved by ,,A isotherms, absorption and photoluminescence spectra, atomic force microscopy imaging, scanning tunneling microscopy, and low-angle X-ray diffraction. Our experimental results indicate that stable, well-defined, and well-organized Langmuir and LB films are formed in pure water and POM subphases, and the presence of Eu-based POM in the subphase causes an area expansion. It is proposed that a lamellar layered structure exists for the PtP/BA/POM LB film in which the POM and PtP molecules can lay down with the interfacial planes. Luminescence spectra of the prepared hybrid LB films show that near-white emission spectra can be obtained due to the dual-emissive nature of the mixed PtP/POM blends. These Pt-polyyne-based LB films displayed interesting electric conductivity behavior. Among them, PtP/BA/POM 13-layer films showed a good electrical response, with the tunneling current up to ±100 nA when the voltage was monitored between ,1 and 7 V. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 879,888, 2010 [source] Development and characterization of an all-olefin thermoplastic sandwich composite systemPOLYMER COMPOSITES, Issue 4 2002Ganesan Kumar In this investigation an all-olefin thermoplastic sandwich system was developed and characterized. Commingled glass fiber polypropylene (PP) composite was used as skin and HDPE (PE) foam with closed cells as core. Infra-red heating was used for melting the surfaces of the substrates for surface fusion bonding with a cold press. Two tie layer films, viz. ethylene-propylene copolymer (EPC) and HDPE/elastomer blend, were used as hot melt adhesives for bonding the substrates. Single lap shear joints were prepared from PP composite and PE foam adherends with a bonding area of 25.4 mm × 25.4 mm to determine the interface strength. EPC tie layer provided higher bond strength (27.4 kg/cm2) to the all-olefin sandwich system than HDPE/elastomer blend based one (19.7 kg/cm2). For EPC tie layer based sandwiches, a mixed mode a failure was observed in the failed lap shear samples; about 40% is cohesive failure through tie layer, and the rest of failure was adhesive either at PP composite or PE surfaces. Environmental scanning electron micrographs (ESEM) reveal that in the process of surface fusion bonding, PE foam cells in the vicinity of 0.80 mm interphase area were coalesced with high temperature and pressure. No macro level penetration of tie layer melt front into foam cells was observed. As the surface morphology of foam was altered on account of IR surface heating and the PP composite bonding side had a resin-rich layer, the bonding situation was closer to that between two polymer film surface. [source] | ||||||||||