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本論文描述了一系列由銅(I)催化-疊氮-端基炔環加成反應（CuAAC）而生成並具有分子内氫鍵的AABB型共聚主鏈（酰胺-三唑）化合物，並以此研究結構上的預組織對這一系列聚合物的聚合效率、物理性質和超分子性質的影響。 / 從衍生自吡啶-2,6-二甲酰胺或對苯二甲酰對苯二胺的二炔單體61或62與具有醌二疊氮化物單體63或64共聚，可獲得一系列重復單元内含兩個分子内氫鍵並具有不同内部結構的聚（酰胺-三唑）化合物。此外，一系列結構相似但重復單元内不含分子内氫鍵的二炔單體65-69也被用於與63或64共聚以作比較。透過核磁共振光譜法，質譜法，和/或尺寸排阻排阻色譜法（SEC）的鑑定能確認所有份子的結構。通過SEC分析結果顯示，只有每個重復單元内含分子内氫鍵的單體61或62得到的相應點擊聚合物才具有較高的DP值。這些結果表示，分子間的氫鍵能增強化合物結構的剛性從而減少環狀聚合物的產生，因而提高聚合度。 / 我們還發現，這些具預組織能猶的骨架的可以提升它們的自組裝能力，並促使它們在芳香溶劑裏形成可逆的有機凝膠。我們採用傅里葉轉換紅外光譜（FTIR）、X-射線粉末衍射（XRD）和掃描電子顯微鏡（SEM）對自組裝機制進行了研究。相比之下，重復單元内不含足夠分子内氫鍵的結構類似物65-69卻不能形成凝膠。 / 最後，我們發現，含有三唑基間苯二甲酰間苯二胺或三唑基吡啶-2,6-二甲酰胺基的聚（酰胺-三唑）化合物可以利用酰胺的NH和三唑的CH形成多個可結合滷素陰離子的位點。我們先用結構更簡單的寡聚類似物113-114和118模仿滷素陰離子(氯、溴、碘)結合強度，模式和機制。結果顯示，寡聚類似物與氯離子的結合強度明顯高於溴陰離子、碘陰離子是最弱的。有趣的是，間苯二甲酰間苯二胺的類似物對滷素陰離子的結合能力比吡啶-2,6-二甲酰胺類似物高得多。表明預組織的酰胺NH和三唑CH並沒有提供明顯對陰離子結合的優勢。相反，含有氮孤對的吡啶-2,6-二甲酰胺系統對滷素陰離子的結合的不穩定性影響更突出。根據此訊息，聚合物對滷素陰離子的結合特性就能得以估計。這研究結果得出一系列少數具有陰離子封裝能力的中性聚合物。 / This thesis described the copper(I)-catalyzed alkyne-azide AABB-type copolymerization of a series of main-chain poly(amide-triazole) compounds containing intramolecular hydrogen bond motifs, with the aim of understanding the effects of hydrogen bond-promoted preorganization on polymerization efficiencies and their physical and supramolecular properties. / A dialkyne monomer, 61 or 62 derived from pyridine-2,6-dicarboxamide or terephthalamide with two intramolecular hydrogen bonds per repeating unit, were synthesized and copolymerized with a diazide monomer, 63 or 64 respectively, to give the corresponding poly(amide-triazole)s (99 and 106) with different internal architecture. For comparison purposes, structurally similar dialkyne monomers 65-69 but with only one or no intramolecular hydrogen bonds per repeating unit were also prepared and copolymerized with the same diazide monomer 63 or 64 to give polymers 100-103 and 107. All compounds were characterized by a combination of nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and/or size exclusion chromatography (SEC). According to SEC analysis, it was found that monomers 61-62, with two intramolecular hydrogen bonds per repeating unit gave the corresponding click polymers with higher DP values. These results indicated that the imposed structural rigidity created by the intramolecular hydrogen bonds could reduce the amount of cyclic polymers and enhance the propagation growth of the polymerization process. / It was also discovered that such a preorganization along the backbone of poly(amide-triazole)s could enhance their self-assembly process and promote the formation of thermoreversible organogels in aromatic solvents. The assembly mechanisms were investigated by Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The organogelating property was not observed in other structural analogues (100-103 and 107) that lack the sufficient number (i.e. 2 per repeating unit) of intramolecular hydrogen bonds. / Finally, it was found that poly(amide-triazole)s that contained repeating triazolyl isophthalamide or triazolyl pyridine-2,6-dicarboxamide motifs could utilize the amide NH and triazole CH groups to form multiple binding sites for halide anions. The halide (Cl⁻, Br⁻, I⁻) binding strengths, modes and mechanisms were first modeled using the structurally simpler oligomeric analogues 113-114 and 118. It was found that the binding strength of the chloride anion was higher than that of the bromide anion, and that of the iodide anion was the weakest. Interestingly, the isophthalamide analogues possessed a much higher binding ability towards anions than the pyridine-2,6-dicarboxamide analogues, suggesting preorganization of the amide NH and triazole CH groups did not offer substantial advantages towards anion binding. Rather, the destabilizing effect of the nitrogen lone pair on the pyridine-2,6-dicarboxamide system was more prominent. Based on this information, the binding properties of the polymeric analogues were then formulated. These results represent one of the few examples of a class of neutral polymers that possessed anion binding ability. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Yim, Sui Lung. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 150-156). / Abstracts also in Chinese.

OH-stretching spectra of various vapour phase species were recorded to investigate hydrogen bonding. The species studied include 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, acetylacetone, hexafluoroacetylacetone and the complex formed in the heterogeneous mixture of methanol and trimethylamine. The spectra range from the infrared, near infrared to visible wavelengths. The main focus of this study is in the near infrared region, in which the OH-stretching overtones are dominant. The near infrared and visible spectrum of formic acid has been recorded to investigate coupling across bonds, specifically a resonance occurring between OH- and CH-stretching vibrations. The same resonance was also observed in the spectrum of 1,2-ethanediol. The spectra of deuterated isotopomers of formic acid and 1,2-ethanediol were recorded to experimentally verify the resonance. The inherently weak nature of the vibrational overtone transitions required sensitive spectroscopic techniques to observe the spectra. The spectra were recorded with conventional long path length absorption spectroscopy and intracavity laser photoacoustic spectroscopy. Anharmonic oscillator local mode calculations of the OH-stretching transitions were performed to simulate the observed spectra. These calculations require calculation of potential energy surfaces and dipole moment functions. Simulated spectra obtained with highly correlated ab initio methods and large basis sets have yielded the best agreement with observation.

The thermodynamic and structural effects of highly anisotropic, short-ranged attraction are investigated for single- and four-site interaction models using Wertheim's multi-density graph theory of chemical association. Both models consist of associating hard spheres, where the saturable attraction sites are described by conical wells centered in the hard core and evaluated in the "sticky-spot" limit. The resulting fluids then mimic many of the directional and steric-constrained properties of hydrogen-bonded fluids. The single-site model is used to explore the effects of dimerization upon the well-known properties of a planar liquid-vapor interface. Apart from hard sphere repulsion and sticky-spot attraction, a van der Waals-like dispersion interaction is incorporated to generate the critical point. Association is treated within Wertheim's thermodynamic perturbation theory, along with classical density functional methods to determine the interfacial density profile. The direct correlation functions which carry all bonding information are derived by means of the associative Ornstein-Zernike equations with a Percus-Yevick-like closure relation. The primary effects of dimerization are manifest in system thermodynamics. Critical temperatures and densities are shifted from their non-associating values and small, non-monotonic shifts in the correlation length and surface tension are also observed. While these effects are accompanied by interface compositional changes, any influence upon the density profile seems to be subsumed by use of the proper T/T[subscript c]. The four-site, network-forming model is investigated as a prototype for the thermodynamics and structural properties of water. Bonding interactions occur between "hydrogen" and electron "lone pair" sites described in the sticky-spot limit. System properties are derived under the ideal network approximation using the same methods as for the one-site model and are found to qualitatively reproduce some thermodynamic and connectivity features characteristic of real water. Partial densities are calculated self-consistently within the theory, and most thermodynamic quantities can be written in terms of the average number of hydrogen bonds per molecule. An analytical structure factor is also derived for this model. / Graduation date: 2003

The main goal of this thesis was to explore the role of H-bonding interactions in ferrocene peptide conjugates at the molecular and supramolecular level. With the help of detailed spectroscopic and crystallographic studies, the intermolecular association of a range of conjugates was studied and described here. It was shown that C-terminal modifications directed the supramolecular assembly. In the case of Fc[CO-Gly-Val-OH]2, the C-terminal carboxylate group directed intermolecular interactions, causing formation of a supramolecular architecture that was characterized by large solvent-filled hydrophobic channels. In the absence of this directional group, as was the case in Fc[CO-Leu-Val-OMe]2 extended β-sheets were formed. Hierarchical self-assembly of disubstituted ferrocene peptide conjugates possessing Gly-Val-Phe and Gly-Val-Phe-Phe peptide substituents gave rise to nano- and micro-sized assemblies. Spontaneous self-assembly of Fc-peptides through intra-and intermolecular hydrogen bonding interactions induced supramolecular building blocks, which further associated to fibers, large fibrous crystals, and twisted ropes. Next, intermolecular H-bonding interactions were studied using a surface-based approach. A fragment of the amyloid-beta (Aβ) peptide was bound to a gold surface through a C-terminal Cys. Various aspects of the peptide film were examined using different electrochemical and surface analytical techniques. The interaction of Congo red and of Lys-Leu-Val-Phe-Phe with the immobilized Aβ fragment was studied using electrochemical methods, showing responses that indicated intermolecular interactions. This surface approach was used to probe the interaction of a series of ferrocene peptides (Fc-CO-Leu-Val-Phe-Phe-OX and Fc-CO-Lys(Boc)-Leu-Val-Phe-Phe-OX with X=H and Me) with the surface-bound Aβ fragment. Biomolecular interactions between Fc-peptides and the Aβ-modified surface were studied by electrochemical methods. The current response of the Fc redox process was modulated by the interaction with the Aβ-modified surface.

We have prepared a new class of polybenzoxazine based nanocomposites through DNA-like self-complementary multiple hydrogen bonding. At first, benzoxazine containing thymine (Bz-T), PEO containing adenine (PEO-A) group and POSS containing adenine (POSS-A) have been successfully synthesized, respectively. Those chemical structures were confirmed by 1H and 13C NMR and FT-IR spectroscopies. DSC and TGA analyses showed that the Bz-T had lower cross-link temperature and higher thermostability than benzoxazine containing methyl acrylate (BZ-ac) group. Moreover, TEM and WAXD provided a new evidence for linearly structure and self-assembly polybenzoxaine through self-complementary multiple hydrogen bonding of its T units. Then, PEO-A/PBz-T and POSS-A/PBz-T hybrid materials were prepared. SAX, WAXD, TEM and AFM analyses indicated that the size of PEO domain in PBz-T matrix was significantly decreased and the new type phase separation boundary (discrete domain through non-convent bonds) was obtained. Finally, we were using WAXD, TEM, DSC and nanoindenter to study properties of POSS-A/PBz-T nanocomposite. The presence of self-assembly nano-lamellate structure and enhance the mechanical properties on thin film, because of well-dispersion of POSS in PBz-T matrix through strong hydrogen bonding between A-T interactions.

Thesis (M.S.)--University of North Carolina at Wilmington, 2004. / Includes bibliographical references (leaves : [56]-57).