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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Synthesis of structurally controlled hyperbranched polymers through the design of new monomers with hierarchical reactivity / 反応性の序列を有するモノマー設計による構造制御された多分岐重合体の合成

Lu, Yangtian 23 July 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22014号 / 工博第4626号 / 新制||工||1721(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 山子 茂, 教授 辻井 敬亘, 教授 竹中 幹人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
82

Towards Early State Disease Detection in Microdevices: Fabrication and Testing of Micro Total Analysis Systems for Bioanalytical Applications

Pan, Tao 07 May 2007 (has links)
The past few years have seen a rapid expansion in interest in the characterization of the entire complement of proteins, or proteome. Micro total analysis systems (μTAS) are an emerging promising method, offering rapid, sensitive and low sample consumption separations. I have demonstrated microchip capillary electrophoresis (CE) devices made of CaF2. New methods have been developed for micromachining enclosed capillaries in CaF2. CE analysis of fluorescently labeled amino acids was used to illustrate bioanalytical applications of these microdevices. Initial on-chip infrared spectroscopy results for qualitative analyte identification were achieved in microfluidic CaF2 channels. I have also shown the evaluation of poly(methylmethacrylate) (PMMA) and thermoset polyester (TPE) microchips for use in protein profiling. To improve separation efficiency and reduce protein adsorption, dynamic coating and poly(ethylene glycol) (PEG) grafting using atom transfer radical polymerization (ATRP) have been used in PMMA microdevices. Proteins, peptides and protein digests have been separated electrophoretically in these PMMA microchips. My results demonstrate that PMMA microdevices should be well suited as microfluidic systems for high performance separations of complex biological mixtures. In-channel ATRP has been developed for the surface modification of TPE microdevices. Characterization indicates that PEG-modified microchannels have much lower and more pH-stable electroosmotic flow, more hydrophilic surfaces and reduced nonspecific protein adsorption. CE of amino acid and peptide mixtures in these PEG-modified TPE microchips had good reproducibility. Phosducin-like protein and phosphorylated phosducin-like protein were also separated to measure the phosphorylation efficiency. My results show that PEG-grafted TPE microchips have broad potential application in biomolecular analysis. Cancer marker analysis is important for medical research and applications. I report a method that can covalently attach appropriately oriented antibodies of interest on monolith surfaces. To reduce nonspecific adsorption, protein solutions were used to effectively block the monolith surface. Selective preconcentration and elution of human chorionic gonadotropin have been performed in my affinity columns, demonstrating that this type of system should have promising applications in cancer marker detection.
83

Copper Catalysis: Perfluoroalkylation and Atom Transfer Radical Polymerization

Paeth, Matthew S. 22 September 2021 (has links)
No description available.
84

Development of New Stereocontrolled Radical Polymerization Using Acid Catalysts / 酸触媒を用いた新しい立体選択的ラジカル重合の開発

Park, Beomsu 24 November 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22847号 / 工博第4787号 / 新制||工||1749(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 山子 茂, 教授 田中 一生, 教授 辻井 敬亘 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
85

Self-Assembled Polymer Materials : From Amphiphile Design to Nanostructure Control / 自己組織化高分子材料 : 両親媒性分子の設計からナノ構造制御へ

Kimura, Yoshihiko 24 November 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22846号 / 工博第4786号 / 新制||工||1748(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 大内 誠, 教授 竹中 幹人, 教授 秋吉 一成 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
86

Molecular Design for Precise Sequence Control and Functions of Alternating Copolymers / 交互共重合体の配列精密制御と機能創出に向けた分子設計

Nishimori, Kana 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22470号 / 工博第4731号 / 新制||工||1739(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 大内 誠, 教授 秋吉 一成, 教授 竹中 幹人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
87

Carbohydrate Mediation of Aqueous Polymerizations: Cyclodextrin Mediation of Aqueous Polymerizations of Methacrylates

Madison, Phillip Holland IV 01 August 2001 (has links)
Cyclodextrin mediation offers a unique mechanism with the potential for interesting control of reaction parameters. Cyclodextrin mediation of hydrophobic monomers may offer desirable kinetics over conventional free radical polymerizations, and it has been shown in this work that cyclodextrin mediation facilitates polymerization of hydrophobic monomers in aqueous solution and in ethylene glycol. It also may be a facile method for controlling relative reactivity of comonomer mixtures. In addition, complexation of cyclodextrin with guest molecules has been utilized in selective synthesis where the host cyclodextrin has been utilized to sterically hinder the attack of certain reactive sites contained within the host cavity. This aspect of inclusion complexation could also be utilized in free radical polymerizations of monomers with multiple reactive double bonds to preferentially reduce the reactivity of the hindered reactive sites. This thesis involves the use of methylated(1.8)-beta-cyclodextrin (MeCD) as a mediator for polymerizations in solvents that would not facilitate polymerization of the pure monomer in the absence of cyclodextrin. This study focuses on the carbohydrate mediation of a series of methacrylic monomers. t-Butyl methacrylate, n-butyl methacrylate, cyclohexyl methacrylate, and 2-ethylhexyl methacrylate were complexed with methylated(1.8)-beta-cyclodextrin and subsequently dissolved in either water or ethylene glycol. The complexes were studied by 1H and 13C NMR spectroscopy, thin layer chromatography, CPK modeling, and thermogravimetric analysis, and were found to have molar ratios of cyclodextrin to monomer as high as 1.0 to 0.72. These complexes were then free radically polymerized in either water or ethylene glycol and resulted in high molecular weight polymers that precipitated out of solution, allowing for facile polymer isolation through filtration. Isolated yields were found to be as high as 86 %. The majority of the cyclodextrin remained in solution after polymerization. It was also recovered and found to be recyclable. Heterogeneous polymerizations were also performed with 2-ethylhexyl methacrylate in which linear dextrin and methylated (1.8)-beta-cyclodextrin were used in emulsifier quantities. It was found that linear dextrin, at concentrations of 3.0 wt% produced a stable latex product with high molecular weight and an isolated yield of >90%. MeCD on the other hand failed to produce a stable emulsion at concentrations between 0.9-3.0 wt%, but remarkably MeCD at 3.0 wt% gave high molecular weight coagulated polymer with a yield of >90%. It is proposed that a heterogeneous mechanism inconsistent with the four major types discussed by Arshady is taking place. Unlike typical suspension or emulsion polymerizations, the cyclodextrin mediated polymerizations are completely homogeneous at the onset, making them more like a dispersion or precipitation polymerization. However, in dispersion and precipitation polymerizations the pure monomer is soluble in the reaction media. In the absence of cyclodextrin, the monomers utilized in this study possessed no appreciable solubility in the reaction media. Therefore, it is proposed that cyclodextrin acts as a phase transfer agent, effectively solublizing the hydrophobic monomer and allowing for the aqueous dispersion or precipitation type polymerization to occur, depending on the relative solubility of the components. Bulk polymerizations of t-butyl methacrylate, cyclohexyl methacrylate, and 2-ethylhexyl methacrylate and their subsequent use in the preparation of carbohydrate/poly(alkyl methacrylate) blends was also performed in this project. Bulk polymers were utilized as references for physical properties for the polymers produced through polymerization of the MeCD/monomer complexes in either aqueous solution or in ethylene glycol. 1H NMR analysis of the polymers from both the cyclodextrin mediation and bulk polymerizations indicated that the tacticity of the polymers produced in both cases were identical. The bulk polymers were also used in the preparation of carbohydrate/methacrylic blends with potential applications in the areas of selective barriers, biodegradable films. Inclusion of drug molecules or antioxidants into these cyclodextrin containing films also may have potential in drug delivery, or food packaging applications. In addition, the side chain liquid crystalline monomer, 6-(4-hexyloxy-biphenyl-4-yloxy)hexyl methacrylate was synthesized in high purity via a three-step procedure and confirmed by a combination of mass spectrometry, thin layer chromatography, and 1H and 13C NMR. This hydrophobic liquid crystalline monomer was subsequently complexed with 1.0-3.0 equivalents of methylated(1.8)-beta-cyclodextrin in an attempt to alter the water solubility of the monomer. Complexes of this side-chain liquid crystalline monomer have not been studied previously and it is proposed that complexation with cyclodextrin will lead not only to novel polymerizations routes for this monomer, but also to novel smectic phases for this thermotropic liquid crystalline polymer. / Master of Science
88

Synthesis and Characterization of Functional Amphiphilic Gradient Copolymers by Atom Transfer Radical Polymerization

Schwitke, Sandra 30 October 2014 (has links)
The purpose of this work was the synthesis of functional amphiphilic gradient copolymers by means of controlled radical polymerizations, more precisely Atom Transfer Radical Polymerization. Two different monomer combinations, tert- and n-butyl methacrylate and tert-butyl and benzyl methacrylate, were copolymerized. In a first step seven different linear statistical copolymers were synthesized by means of batch polymerization. They were used as comparative material and the analysis of the reaction kinetic yielded the effective rate constants and the copolymerization parameters of the monomers in the particular monomer systems. Furthermore required for gradient polymer syntheses AB-di-block copolymers were synthesized as a second kind of comparative material. With the results of the kinetic analysis the monomer addition programs for the semibatch polymerizations were calculated to prepare gradient copolymers. Four different gradient copolymers with different compositions of tBMA and nBMA (ftBMA= 0.5, 0.65, 0.75, 0.85) and one gradient copolymer of tBMA and BzMA (ftBMA= 0.5) were synthesized. All semibatch reactions proceeded controlled, i. e. with mostly suppressed termination reactions. The compositions of the resulting copolymers exhibited ''double-gradients''. The point of change of the compositions were located at 16%, respectively 11% of conversion. The effective compositional gradients φ = dF1/dp were φ = 0.53, 0.46, 0.28, 0.15 and 0.43. A systematic correlation between the thermal behavior of the gradient copolymers and their composition was not found, as opposed to the statistical and the di-block copolymers. Semibatch synthesis with online infrared-spectroscopy observation to control the monomer feed during the synthesis were used for the polymerization of gradient copolymers. It was not possible to calculate the change of compositions of the polymers because it was not known how much monomer was injected at a certain time of the polymerization. A second problem was that the experimental set-up was not gas-tight. Hence, oxygen led to termination reactions. Three different kinds of hydrolysis were investigated for the cleavage of the tert-butyl groups on the polymer chains. The obtained gradient copolymers were hydrolyzed with methanesulfonic acid to obtain the intended amphiphilic polymer chains. All reactions proceeded with quantitative conversion. Hence, functional amphiphilic copolymers were obtained.
89

Supramolecular Self-Assembly of Well-Defined Polymers:Positional Programming of Complementary Hydrogen Bonds / 精密に制御された高分子の超分子自己組織化: 相補的水素結合の位置制御

Lee, Sang-Ho 23 July 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18518号 / 工博第3910号 / 新制||工||1600(附属図書館) / 31404 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 澤本 光男, 教授 伊藤 紳三郎, 教授 中條 善樹 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
90

Fabrication of Well-Defined Architectures of Ultrahigh-Molecular-Weight Polymers by Living Radical Polymerization / リビングラジカル重合により合成した超高分子量ポリマーの高次構造形成

Hsu, Shu-Yao 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19748号 / 工博第4203号 / 新制||工||1648(附属図書館) / 32784 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 辻井 敬亘, 教授 山子 茂, 教授 渡辺 宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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