This paper demonstrates the feasibility of high-throughput investigation of ionic conductivity in oxygen-ion conductors. Yttria stabilized zirconia (YSZ) composition-spread thin films with nanometer-size grains were prepared by 90° off-axis reactive RF cosputtering. We compare results for two electrode configurations, namely, out-of-plane (parallel plate) and in-plane (planar interdigitated electrode) and find that the contribution from the intragrain conductivity in YSZ thin films (150 nm) is more explicit in the latter configuration because it greatly diminishes electrode effects. The intragrain oxygen ion conductivity of thin film YSZ was systematically measured as a function of yttria concentration over the range 2 mol % to 12 mol %. The results show that the measured conductivity of the YSZ thin films is close to that of corresponding bulk materials with a peak value around 3 × 10⁻⁴ S cm⁻¹ at 440 °C at the optimum Y₂O₃ concentration of 8 mol %. Validation of this technique means that it can be applied to novel chemical systems for which systematic bulk measurements have not been attempted.
Polymer-grafted nanoparticles (PGNs) receive great attention because they possess the advantages of both the grafted polymer and inorganic cores, and thus demonstrate superior optical, electronic, and mechanical properties. Thus, PGNs with tailorable interparticle interactions are indispensable for the formation of a superlattice with a defined and ordered structure. In this work, the synthesis of PGNs is reported which can form interparticle hydrogen-bonding to enhance the formation of well-defined 2D nanoparticle arrays. Various polymers, including poly(4-vinyl pyridine) (P4VP), poly(dimethyl aminoethyl acrylate) (PDMAEMA), and poly(4-acetoxy styrene) (PAcS), are attached to silica cores by a "grafting from" in a mini emulsion-like synthesis approach. SiO 2 -PAcS brushes are deprotected by hydrazinolysis and converted into poly(4-vinyl phenol) (PVP), containing hydroxyl groups as potential hydrogen-bonding donor sites. Understanding and controlling interparticle interactions by varying grafting density in the range of 10 −2 -10 −3 chain nm −2 , and the formation of interparticle hydrogen bonding relevant for self-assembly of PGNs and potential formation of PGN superlattice structures are the motivations for this study.
Poly(styrene-co-N-maleimide) copolymers bearing tert-butoxycarbonyl (t-BOC)-protected amine groups attached to side chains of varying lengths are synthesized via activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP) and investigated from the perspective of photoresist applications. The length of the alkyl substituents enables control of thermal properties as well as hydrophobicity, which are critically important for resist processing. Removal of the acid labile t-BOC group during deep-UV (DUV)exposure shifts solubility in the exposed areas and well-defined line space patterns of 1 μm are obtained for the selected copolymers. The correlation between glass transition temperature (T g ) and solubility contrast determines the lithographic performance where the copolymers with shorter alkyl chains exhibit promising results.
Activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP)-based aqueous miniemulsion polymerization where the polymerization takes place in the stabilized monomer droplets is described. In this work, we compared styrene, n-butyl methacrylate (nBMA) and tert-butyl methacrylate (tBMA) and investigated the influence of their hydrophobicity on dispersity, molecular weight and particle stability based their partition coefficients (logP) (2.67, 2.23, and 1.86, respectively). Tetrabutylammonium bromide (TBAB) was used as a phase transfer agent for the controlled delivery of Cu 2+ -Br/tris(2-pyridylmethyl)amine (TPMA), a hydrophilic catalyst, into monomer droplets of varying hydrophobicity. The resulting dispersity and particle stability
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