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Thorough studies of RAFT copolymerization in a continuous flow to gain deeper insights into kinetics, reactivity, and applicability were conducted with monomers and solvents utilizable for chemically amplified resist systems.

The goal of this study is to examine the roles of Zimbardo's time perspective along with other individual differences such as promotion focus and innovativeness in perceived ease of use, perceived usefulness, and attitude toward SNSs (social networking sites) in the technology acceptance model (TAM). A total of 234 participants joined this online study in South Korea. As predicted, past positive time perspective (TP) positively affected promotion focus and innovativeness, whereas past negative TP negatively affected them. Present hedonic TP positively affected innovativeness, and present fatalistic TP negatively affected promotion focus each. Future TP also positively related to promotion focus and innovativeness. In addition, simple and serial mediation effects of perceived ease of use and perceived usefulness independently and sequentially mediated the impact of TP on attitude toward SNSs. By considering TP along with promotion focus and innovativeness in conjunction with beliefs in the TAM, this study identifies psychological underpinnings of how individual differences affect technology adoption attitude and behavior. Research implications and future research suggestions will be discussed in detail.

A highly fluorinated alternating polymer, P(RFMi-St), possessing improved thermal properties and patterning capabilities over perfluoroalkyl polymethacrylates under high energy radiation was achieved with semi-perfluorododecyl maleimide (RFMi) and styrene (St). RFMi could be synthesised efficiently via a Mitsunobu reaction condition and copolymerised with St by free radical and reversible-deactivation radical polymerisation protocols. P(RFMi-St) showed a satisfactory glass-transition temperature (108 °C) and intermolecular cross-linking behaviour under electron-beam and commercially more important extreme UV (λ = 13.5 nm) irradiation. The exposed regions lost their solubility, resulting in the successful formation of mechanically non-deteriorated negative-tone images down to 50 nm. In addition, P(RFMi-St) could be solution-processed with chemically non-damaging fluorous liquids, which enabled the polymer to be applied effectively on top of an organic semiconductor layer as a dielectric material (dielectric constant 2.7) for the organic field-effect transistor fabrication.

This study investigates the effects of the social comparison orientation in social networking sites on psychological well-being. In particular, it examines the mediation effect of perceived social support and self-esteem in the relationship between social comparison orientation and psychological well-being. Data were collected through an online survey with 236 participants in South Korea. The results showed that social comparison orientation negatively influenced psychological well-being. In the relationship between social comparison orientation and psychological well-being, perceived social support had no mediation effect, self-esteem had a significant negative mediation effect, and perceived social support and self-esteem had a negative serial mediation effect. The social comparison orientation in social networking sites could elicit negative emotions, which decrease perceived social support, self-esteem, and psychological well-being. Theoretical and practical implications as well as suggestions for future studies are discussed in detail.

Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of the dopant counterions. Here, we present a combined experimental and theoretical study rebutting this belief. Using a newly developed doping technique based on ion exchange, we prepare highly doped films with several counterions of varying size and shape and characterize their carrier density, electrical conductivity, and paracrystalline disorder. In this uniquely large data set composed of several classes of high-mobility conjugated polymers, each doped with at least five different ions, we find electrical conductivity to be strongly correlated with paracrystalline disorder but poorly correlated with ionic size, suggesting that Coulomb traps do not limit transport. A general model for interacting electrons in highly doped polymers is proposed and carefully parametrized against atomistic calculations, enabling the calculation of electrical conductivity within the framework of transient localization theory. Theoretical calculations are in excellent agreement with experimental data, providing insights into the disorder-limited nature of charge transport and suggesting new strategies to further improve conductivities.

High-mobility low-hysteresis electrolyte-gated thin-film transistors were successfully fabricated using a diketopyrrolopyrrole (DPP) and benzotriazole (BTz) copolymer semiconductor and high-capacitance ion gels based on 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([EMI][TFSI]) and tetraoctyl phosphonium ([P8888]) [TFSI]. The DPP-BTz transistors gated with both ion gels operated effectively at low voltages below 1V with high on-to-off current ratios exceeding 105 and very low device hysteresis. Specifically, when the [EMI][TFSI] ion gel was employed as a gate dielectric layer, the DPP-BTz transistors exhibited a very high carrier-mobility value of 8.50 ± 1.09 cm2/Vs. In addition, device hysteresis of the DPP-BTz transistor was almost invariant to the voltage sweeping rate and was much lower than that of the poly(3-hexylthiophene) (P3HT) transistor under the same conditions. Overall, these results indicate that the performance of electrolyte-gated transistors can be improved using the DPP-BTz semiconductor.

This paper presents a new surface modification strategy to develop a poly(ethylene terephthalate) (PET)-based membrane having a hydrophilic surface, high nutrient ion permeability, sufficient mechanical strength, and organic fouling resistance, using an anthracene (ANT)-attached polyethylene glycol (PEG) surface modification agent (SMA) synthesized in this work. During the modification process, the ANT parts of the SMAs poke through and anchor to the surface of a commercial PET woven fabric via physical interactions and mechanical locking. The PEG chain parts coat the surface in the brush and arch forms, which generates a hydration layer on the fabric surface. The consequently obtained surface property and unique structure of the modified PET-based membrane result in higher nitrate ion permeability, organic fouling resistance, and microalgae production compared to those of the unmodified one. These are also affected by the molecular weight of the PEG and the number density of the anchored SMAs. The study demonstrates that this new surface modification method has the potential to allow the development of a desirable PET-based membrane for the efficient massive production of marine microalgae.

The multiscale morphology and device performance of printed semiconducting polymers are highly sensitive to the substrate/ink interfacial properties during solution coating. There is an urgent need for general design rules correlating the substrate properties and conjugated polymer (CP) morphology, which do not yet exist. Dynamic surfaces are particularly promising for templating highly crystalline and highly aligned conjugated polymer thin films and have been shown in recent studies. Herein, we implement the dynamic-templating method using a series of liquid-infused nanoporous substrates as a tool to study the impact of template reconfigurability and chemistry on the multiscale morphology of conjugated polymer thin films, using a high performing donor–acceptor polymer (DPP-BTz) as a model compound. By quantifying the enthalpy of adsorption, we demonstrate that the strength of template–CP interactions directly measures the effectiveness of dynamic surfaces in promoting conjugated polymer crystallization and alignment. We further show that the enthalpy of interactions increases by enhancing the template dynamics and is sensitively modulated by template chemistry. Specifically, increasing the template–CP interactions leads to a larger domain size and higher degree of crystallinity in templated conjugated polymer thin films prepared by meniscus-guided solution coating. This observation validates our hypothesis that dynamic templates function by promoting the nucleation of conjugated polymers. We also demonstrate that such dynamic-template-dependent morphology is independent of coating speed. Notably, the enhanced morphological properties modulate the charge carrier mobility in field-effect transistors (FETs) over an order of magnitude reaching a hole mobility of 2.8 cm2 V−1 s−1. This work is a significant step towards establishing general guidelines on how the substrate–ink interfacial properties influence morphology and performance of solution coated CP thin films.

We report the synthesis, operating mechanism, and application of a copolymer that reveals increasing solubility in fluorous solvents by photolysis. The copolymer, PFBI, was prepared by polymerizing perfluorooctyl methacrylate (FOMA), benzilmonooxime methacrylate (BMOMA) and isobornyl methacrylate (IBMA). It showed a solubility of bigger than 20% (w/v) in a fluorous solvent, 1,1,1,2,3,3-hexafluoro-4-(1,1,2,3,3,3-hexafluoropropoxy)pentane (PF-7600), and the solution could be spin-cast to form 1.5 μm-thick films. When 365 nm UV light was irradiated onto it, 7 μm size stencil patterns could be formed after the UV-exposed regions were washed out with a fluorous solvent of a weaker dissolving power. To verify the responsible chemical mechanism for this increasing solubility, PFBI after UV irradiation was checked by size exclusion chromatography (SEC); no significant molecular weight decrease could be observed. This result suggested that UV exposure may cause the cleavage of the benzilmonooxime moieties, the side units, rather than significant polymer main-chain scission to increase the solubility. As an example of useful applications, PFBI was employed as a stencil material to produce micro-patterned quantum dot (QD) films. After casting a PFBI thin film on a Si substrate, wells for holding the QD ink were formed by UV exposure. After a red QD solution was deposited on the template by spin-coating, the stencil was removed by dissolution in a fluorous solvent, resulting in the 60 μm-sized red QD film arrays. The same steps were repeated with a green QD solution, and two colour QD film arrays could be built successfully. This result demonstrates that PFBI can be applied as a useful patterning material in the organic and printed electronics field.

With the growth of consumer skepticism toward advertising, marketers have begun implementing native advertising. Drawing on the Persuasion Knowledge Model (PKM), this study examines how content typ...

Investigations to evaluate the extreme ultraviolet (EUV) lithographic performance of 160 nm thick poly(methyl methacrylate) with 13.5 nm wavelength EUV light were performed using a synchrotron radiation source at Pohang Light Source-II (PLS-II). The single system enabled the determination of the sensitivity, contrast, linear absorption coefficient, critical dimension, and line edge roughness of polymer thin films through tests and measurements. The experimental findings were also compared to theoretical results and those of previously reported studies. According to the results of the dose-to-clear test and transmission measurements, the critical dimension of a line and space pattern (50 nm)

In this report, we present an enzyme deposited Au electrode for an electrochemical measurement of acetylacetic acid (AcAc) in urine. The electrode has an immobilized layer of a mixture of D-β-hydroxybutyrate dehydrogenase (HBDH) and nicotinamide adenine dinucleotide (NADH) as sensing material to investigate its electroanalytical properties by means of cyclic voltammetry (CV). The modified electrodes are used for the detection of AcAc and present a linear current increase when the AcAc concentration increases. The electrode presents a limit of detection (LOD) of 6.25 mg/dL in the range of 6.25–100 mg/dL for investigation of clinical relevance. Finally, the electrode was evaluated using 20 patient samples. The measured results of urine ketone by the developed electrode were compared with the clinical results from a commercial kit, and the analysis showed good agreement. The proposed electrode was demonstrated to be a very promising platform as a miniaturized electrochemical analyzer for point-of-care monitoring of the critical biochemical parameters such as urine ketone.

Dynamic surfaces play a critical role in templating highly ordered complex structures in living systems but are rarely employed for directing assembly of synthetic functional materials. We design ion gel templates with widely tunable dynamics ( Tg) to template solution-coated conjugated polymers. We hypothesize that the ion gel expedites polymer nucleation by reconfiguring its surface to facilitate cooperative multivalent interactions with the conjugated polymer, validated using both experimental and computational approaches. Varying ion gel dynamics enables large modulation of alignment, molecular orientation, and crystallinity in templated polymer thin films. At the optimal conditions, ion-gel-templated films exhibit 55 times higher dichroic ratio (grazing incidence X-ray diffraction) and 49% increase in the relative degree of crystallinity compared to those templated by the neat polymer matrix. As a result, the maximum hole mobilities increase by factors of 4 and 11 along the π-π stacking and the backbone directions. Intriguingly, we observe a synergistic effect between the gel matrix and the ionic liquid that produces markedly enhanced templating effect than either component alone. Molecular dynamics simulations suggest that complementary multivalent interactions facilitated by template reconfigurability underlie the observed synergy. We further demonstrate field-effect transistors both templated and gated by ion gels with average mobility exceeding 7 cm2 V-1 s-1.

The patterning of organic materials on solid substrate surfaces has been demonstrated by several methods, such as photolithography, soft lithography, imprint lithography and ink-jet printing. Fluorinated polymers and solvents provide attractive material systems to develop new patterning approaches, as they are chemically orthogonal to non-fluorinated organic molecules, allowing their efficient incorporation in different devices and systems. Moreover, fluorinated polymers are soluble in hydrofluoroether solvents, benign to biomolecules, and can be properly engineered to enable efficient photolithographic patterning. In this work, we report the development of a new photolithographic process for patterning biomolecules on any kind of surfaces either by physical adsorption or covalent bonding. The photoresist is based on a fluorinated material and hydrofluoroether solvents that have minimum interactions with biomolecules and thus they can be characterized as orthogonal to the biomolecules (bio-orthogonal). In both cases, the creation of patterns with dimensions down to 2 μm was achieved. The implementation of the developed photolithographic procedure for the creation of a multi-protein microarray is demonstrated.

This research examined the effect of native ads on consumer brand engagement – specifically, how source disclosure of ad sponsors affected consumers’ perceived ad deceptiveness as well as their att...

Purpose The purpose of this paper is to investigate the impact of country-of-origin (COO) fit and consumer product knowledge on consumer brand attitudes in a cross-border strategic brand alliance (SBA). Design/methodology/approach An experimental study with 207 subjects was conducted using a series of 2 (COO fit: low vs high COO fit) by 3 (product knowledge: low vs moderate vs high knowledge) by 2 (time: pre- vs post-alliance attitudes) mixed factorial design. Findings The impact of COO fit on pre- and post-alliance changes in attitude toward the partner brand showed a nonlinear relationship from high-, to moderate-, to low-knowledge consumers. High COO fit significantly and positively affected pre- and post-alliance changes in attitude toward the partner brand more for high- and low-knowledge consumers than for moderate-knowledge consumers. In contrast, low COO fit significantly and positively affected pre- and post-alliance changes in attitude toward the partner brand more for moderate-knowledge consumers than for high- and low-knowledge consumers. Practical implications The effectiveness of cross-border SBAs differs with consumer product knowledge. For high- and low-knowledge consumers, high COO fit information had greater impact than low COO fit information in their product evaluation. However, when targeting moderate-knowledge consumers, providing sufficient product-related attribute information would help them to generate a favorable brand attitude. Originality/value This study attempted to identify the complex relationship between COO fit and consumer product knowledge on the consumer decision-making process.

In this presentation, we show our efforts toward the discovery of extreme UV (EUV) resists based on the radical reactions that highly fluorinated molecular units undergo. Recently, we reported that small molecules equipped with perfluoroalkyl ether (PFAE) chains or fluoroarene units show solubility change under high-energy electron beam (e-beam) or EUV light via intermolecular chemical network formation. Although this non-chemical amplification-type imaging mechanism worked without the help of any catalytic species, its low sensitivity characteristics had to be improved for practical use. A solution was sought in polymeric resist platforms, particularly those possessing a uniform composition and high enough glass transition temperature (Tg). A perfluoroalkyl moiety was introduced to maleimide (Mi) to give RFMi, which could then be copolymerized in an alternating manner with styrene (P1) and a styrenic derivative containing a Sn atom (P2) or acid-labile protective group (P3). By using a reversible deactivation radical polymerization method, the copolymers could have narrow molecular weight distributions (polydispersity index (PDI) < 1.5) along with their uniform monomer compositions. Thanks to the rigid backbone structure enabled by the maleimide units, the perfluoroalkylated copolymers could be characterized by high Tgs over 100‡C. When lithographic patterning tests were performed under EUV exposure conditions, the thin films of all the alternating copolymers could be tailored down to the 30-nm size, and in particular, the one with Sn atoms (P2) made patterns with 22 mJ/cm2. These results demonstrate the useful nature of the imaging chemistry that highly fluorinated molecular units enable under high energy radiation.

Nowadays, the display industry is endeavoring to develop technology to provide large-area organic light-emitting diode (OLED) display panels with 8K or higher resolution. Although the selective deposition of organic molecules through shadow masks has proven to be the method of choice for mobile panels, it may not be so when independently defined high-resolution pixels are to be manufactured on a large substrate. This technical challenge motivated us to adopt the well-established photolithographic protocol to the OLED pixel patterning. In this study, we demonstrate the two-color OLED pixels integrated on a single substrate using a negative-tone highly fluorinated photoresist (PR) and fluorous solvents. Preliminary experiments were performed to examine the probable damaging effects of the developing and stripping processes upon a hole-transporting layer (HTL). No significant deterioration in the efficiency of the develop-processed device was observed. Efficiency of the device after lift-off was up to 72% relative to that of the reference device with no significant change in operating voltage. The procedure was repeated to successfully obtain two-color pixel arrays. Furthermore, the patterning of 15 &mu, m green pixels was accomplished. It is expected that photolithography can provide a useful tool for the production of high-resolution large OLED displays in the near future.

In this presentation, we will show our efforts for the discovery of high-performance imaging reactions based on fluorine and radical chemistry working under high-energy radiation. Prior to this study, we have reported molecular resists equipped with rather flexible perfluorinated alkyl ether (PFAE) chains and their imaging behavior as negative-tone resists under electron beam irradiation. In this study, we turned our attention to another fluorinated unit, fluorinated aromatic compounds, possessing structural rigidity that we believe contributes to achieving improved patterning capabilities. Successful coupling reactions between a phenolic resist core and fluorinated arenes provided fluorinated molecular resists, which we evaluated in terms of imaging behavior under e-beam and EUV lithographic conditions. The solubility of their thin films was decreased by the high-energy radiation; thus, negative-tone patterns down to 30 nm half-pitch could be obtained after development in fluorous solvents.

We report a new materials system for the fabrication of embedded silver grid electrodes with micron-sized linewidth >10 times narrower than can be achieved using the conventional printing techniques of screen, inject and flexographic printing. Using micro-contact printed thin films of the highly fluorinated polymer poly(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl methacrylate) together with low temperature heating of the substrate during metal deposition by thermal evaporation, we have fabricated embedded silver transparent grid electrodes on flexible plastic substrates without the need for a metal etching step or a separate grid-embedding step. This simplified approach to grid electrode fabrication is made possible by the very low condensation coefficient of Ag on areas of the substrate covered with the printed organofluorine layer, removing the need for harmful chemical etchants and slow chemical intensive electrochemical deposition steps.

Dynamic-template-directed assembly is a promising method to enhance molecular ordering and electronic properties of solution-coated polymer semiconductor thin films over a large area. In this work, we establish that multicomponent dynamic templates of complementary chemistries can promote polymer crystallization through cooperative multivalent interactions. We investigate this phenomenon using a combination of templating substrates including a fluoropolymer, a hydrogen-bonded liquid, and an ionic liquid (IL). Template-dependent multiscale morphology is studied by a comprehensive set of characterization techniques to understand how introducing diverse chemical moieties modulates polymer assembly. Our results clearly confirm synergistic effects between components of complementary chemistries constituting the dynamic template. The relative degree of crystallinity is improved by 50-150% for films deposited on multicomponent dynamic templates compared to their neat constituents. In addition, macroscopic alignment is increased significantly (2-5 times) compared to single-component templates. As a result, highly anisotropic charge transport is observed with apparent hole mobilities up to 3.6 cm2 V-1 s-1. In contrast, such a synergistic effect is not observed when using a multicomponent dynamic template of comparable chemistries (i.e., IL and polymerized IL). We elucidate the origin of this synergistic effect by using attenuated total reflectance Fourier transform infrared spectroscopy and isothermal titration calorimetry. When the dynamic template comprises two or more components interacting with complementary binding sites on the conjugated polymer (CP) (esp. backbone vs side chain), the template-polymer interactions is significantly enhanced compared to the sum of single component contributions. These results provide valuable insights into surface-directed CP crystallization during large-area solution coating. Template dynamics is rarely studied and represents a new opportunity for guiding assembly of soft functional matter.

We report the synthesis, characterization, and photopatterning of high-k inorganic nanoparticles that are covered with highly fluorinated carboxylic acid and, as a result, are solution-processable in fluorous liquids. Barium titanate (BTO) nanoparticles, 7&ndash, 8 nm in diameter, were prepared under solvothermal conditions and were surface-modified with perfluoroalkyl ether-type carboxylic acid molecules via ligand-exchange reactions. Thin films with a high dielectric constant (9.27 at 1 kHz) were achieved by spin-coating homogeneous solutions of BTO nanoparticles in a fluorous solvent (HFE-7500). Additionally, electron-beam lithography and photolithography were applied to the thin films of BTO nanoparticles, yielding BTO patterns with scales of 300 nm and 5 &mu, m, respectively. Thus, an approach for a chemically non-damaging solution process of inorganic materials for device implementation was successfully demonstrated.