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Kazuhiro Nakabayashi Shigeki Sobu Yuji Kosuge Hideharu Mori 《Journal of polymer science. Part A, Polymer chemistry》2018,56(19):2175-2182
This work demonstrates the UV nanoimprinting lithography (UV-NIL) of high refractive index and highly transparent polythioethers based on thiol-ene click chemistry. Herein, 9,9-bis(3-mercaptopropylphenylether)fluorene (BMPF) is designed as a new thiol monomer with a high refractive index, high transparency, and good processability for UV-NIL. Colorless polythioethers are synthesized from BMPF and ene monomers under mild thiol-ene click reaction conditions. Excellent transmittance (96%) of 400 nm light is observed in all the polymer films and high refractive index values of 1.5972–1.6382 are attained. UV-NIL using thiol-ene photopolymerization affords polymer nanoimprinting patterns with various features on the order of 100–500 nm without any fractures. To the best of our knowledge, this is the first report on UV-NIL of high refractive index and highly transparent polymers. Through proper monomer and polymer design, novel polythioethers with suitable glass transition temperature (T g) values are developed with high refractive index, high transparency, and good UV-NIL processability. Furthermore, UV-NIL based on thiol-ene click chemistry is accomplished at the nanoscale. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2175–2182 相似文献
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Mahyar Nasabi Khashayar Khoshmanesh Francisco J. Tovar‐Lopez Kourosh Kalantar‐zadeh Arnan Mitchell 《Electrophoresis》2013,34(22-23):3150-3154
This paper demonstrates the utilization of 3D semispherical shaped microelectrodes for dielectrophoretic manipulation of yeast cells. The semispherical microelectrodes are capable of producing strong electric field gradients, and in turn dielectrophoretic forces across a large area of channel cross‐section. The semispherical shape of microelectrodes avoids the formation of undesired sharp electric fields along the structure and also minimizes the disturbance of the streamlines of nearby passing fluid. The advantage of semispherical microelectrodes over the planar microelectrodes is demonstrated in a series of numerical simulations and proof‐of‐concept experiments aimed toward immobilization of viable yeast cells. 相似文献
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Improved self‐assembly of poly(dimethylsiloxane‐b‐ethylene oxide) using a hydrogen‐bonding additive 下载免费PDF全文
Damien Montarnal Zoltan Mester Christian W. Pester Alaina J. McGrath Glake Hill Glenn H. Fredrickson Craig J. Hawker 《Journal of polymer science. Part A, Polymer chemistry》2016,54(14):2200-2208
Block copolymers with increased Flory–Huggins interaction parameters (χ) play an essential role in the production of sub‐10 nm nanopatterns in the growing field of directed self‐assembly for next generation lithographic applications. A library of PDMS‐b‐PEO block copolymers were synthesized by click chemistry and their interaction parameters (χ) determined. The highest χ measured in our samples was 0.21 at 150 °C, which resulted in phase‐separated domains with periods as small as 7.9 nm, suggesting that PDMS‐b‐PEO is a prime candidate for sub‐10 nm nanopatterning. To suppress PEO crystallization, PDMS‐b‐PEO was blended with (l )‐tartaric acid (LTA) which allows for tuning of the self‐assembled morphologies. Additionally, it was observed that the order‐disorder transition temperature (TODT) of PDMS‐b‐PEO increased dramatically as the amount of LTA in the blend increased, allowing for further control over self‐assembly. To understand the mechanism of this phenomenon, we present a novel field‐based supramolecular model, which describes the formation of copolymer‐additive complexes by reversible hydrogen bonding. The mean‐field phase separation behavior of the model was calculated using the random phase approximation (RPA). The RPA analysis reproduces behavior consistent with an increase of the effective χ in the PDMS‐b‐(PEO/LTA suprablock). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2200–2208 相似文献
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吴世康 《影像科学与光化学》2017,35(1)
表面等离子共振光谱(Surface Plasmon Resonance,SPR)是近年来得到快速发展的一门技术。它是一种无标记的、可用于实时定量检测某些固定于传感芯片上的组分与被结合物种间的绑定亲合度(binding affinity)、且可用于对相对小量物质进行检测的重要手段。由于它可方便地研究不同生物或化学物种的有关反应与动力学问题,因此具有重要的实用意义,受到广泛关注和重视。本文对有关等离子共振现象的形成及其作为敏感检测手段的机制、原理和改进等问题作了简要的介绍。 相似文献
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Tiesheng Li Wenjian Xu Caiqin Tang Min Zhang Yangjie Wu Tokuji Miyashita 《Journal of Polymer Science.Polymer Physics》2012,50(2):139-147
A new series of copolymer poly(N‐hexadecylmeth acrylamide‐co‐bis(anthracen‐9‐ylmethyl) 2‐allylmalonate) [poly(HDMA‐co‐DAnMAMA)]s containing swallow‐tailed double anthracenyl groups and long alkyl group are designed and synthesized. The main route of the photochemical reaction of the p(HDMA‐DAnMAMA)copolymer Langmuir–Blodgett (LB) films is dimerization reaction between the anthracenyl groups under the irradiation of both 365 and 248 nm for limiting irradiation time, resulting to a fine negative‐tone pattern. On the other hand, the anthracenyl groups act just as photodecomposition group under 248 nm for longer irradiation time, resulting to a fine positive‐tone pattern. Consequently, positive‐tone and negative‐tone pattern are obtained by choosing not only a suitable irradiation light wavelength, but the irradiation time at 248 nm. Moreover, it is found that the exposed and unexposed regions of copolymer LB films irradiated at 248 nm have solubility differentiation in gold etchant (I2/NH4I/C2H5OH/H2O), that is to say, the gold photopatterns with the maximal resolution of the used mask can be obtained easily without any development process. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 50: 139–147, 2012 相似文献
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