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Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xix, 193 p.; also includes graphics. Includes bibliographical references (p. 181-193).

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The work described in the thesis is concerned with making new polymeric materials via ring opening metathesis polymerisation (ROMP) using a well-defined ruthenium carbene as an initiator. The object of the study was to provide a process for producing shaped articles by introducing a reactive liquid mixture into a mould in which the reacting liquid mixture undergoes ROMP in the bulk to produce the moulded article. Mono- and difunctional imidonorbomene derivatives were used as monomer and crosslinker respectively. The properties of the cured samples were determined by sol-gel analysis, DSC, TGA, nmr and IR spectrometry. Gel fraction, Tg and content of unreacted monomer were used to characterise the cured samples. The results indicated a strong dependence of the polymers appearance and properties on the polymerization formulation and protocol, i.e. the monomer, the crosslinker and the polymerization conditions. The relative reactivity of the exo- and endo-monomers was investigated using the 'Hnmr technique since the initiation and propagation steps of the polymerisations can be followed in detail by this technique. The results showed that the polymerisations are living and the exo-isomer is more reactive than endo-isomer. A wider range of polymers can be prepared from solution polymerisation as compared to bulk polymerisation. The polymers derived from solid monomers, the monofunctional monomer with short N-alkyl pendant groups and all the difunctional monomers, could be prepared more easily in solution than in bulk polymerisation. The endo-monomer and the monofunctional monomer with long N-alkyl pendant group showed very low reactivity and were not suitable for ROMP in bulk but underwent solution polymerisation. It was found that the thermal properties of the linear polymers depend upon the amount of each monomer isomer incorporated into the polymer chain and the ength of the N-alkyl pendant groups. All linear polymers are soluble in chlorinated solvents from which clear films can be cast. The work described establishes conditions for production of fully crosslinked solids with only traces of the sol fraction.

The first steps towards the long term objective of building entirely synthetic organic/inorganic composite materials in a biomimetic manner have been achieved. Following an introduction and discussion of the background to the work (Chapter 1), the syntheses and characterisation of various molecular weights of both poly(exo, exo-1,4-cyclopentenylene-5,6-ethylidene-2,3-sodium dicarboxylate) and poly(exo,endo-l,4-cyclopentenylene-5,6-ethylidene-2,3- sodium dicarboxylate) and model compounds of their repeat units have been described (Chapters 2 and 4). These compounds were used as additives in the crystallisation of CaCO(_3) from supersaturated aqueous solutions of Ca(HC0(_3))(_2) (Chapters 3 and 5). The work described in Chapter 3 showed that the diacid model compounds used as additives controlled the morphology of calcite crystals grown from supersaturated solutions of Ca(HCO(_3))(_2) over a large range of concentrations of model compound; [Ca(^2+)]: [model compound] 10 to 1000:1. The polymers of these monomers appeared to give the same type of crystal morphology as the isolated model repeat units, however, modification was observed on only one face of the CaCO(_3) crystals. This observation, and the relatively small crystal size distributions measured, indicated that the calcite crystallisation was nucleated beneath the polymer films at the truncated modified face and growth continued down into the solution.

Thesis (Ph.D.)--Tufts University, 2003. / Director: David L. Kaplan. Submitted to the Dept. of Chemistry. Includes bibliographical references (leaves 160-175). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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by Man-Wai Woo. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 77-81). / Abstracts in English and Chinese. / ABSTRACT --- p.i / ACKNOWLEDGMENT --- p.iii / CONTENTS --- p.iv / LIST OF FIGURES --- p.vi / LIST OF TABLES --- p.ix / ABBREVIATIONS --- p.x / Chapter 1. --- INTRODUCTION / Chapter 1.1 --- General Background of Phthalocyanines --- p.1 / Chapter 1.2 --- Previous Examples of Phthalocyanine-containing Polymers --- p.5 / Chapter 1.2.1 --- Poly(phthalocyanines) Linked Via Peripheral Substituents --- p.5 / Chapter 1.2.2 --- Poly(phthalocyanines) Linked Via Axial Ligation --- p.7 / Chapter 1.2.3 --- Poly(phthalocyanines) Attached Laterally to a Polymer Backbone --- p.11 / Chapter 1.3 --- Ring Opening Metathesis Polymerization (ROMP) --- p.15 / Chapter 1.4 --- ROMP of Norbornene Substituted Porphyrazine --- p.18 / Chapter 2. --- RESULTS AND DISCUSSION / Chapter 2.1 --- Phthalocyanines Substituted with Four Poly(norbornene)s --- p.20 / Chapter 2.1.1 --- Preparation of Tetra(norbornene) Phthalocyanines --- p.20 / Chapter 2.1.2 --- Polymerization of Tetra(norbornene) Phthalocyanines --- p.30 / Chapter 2.1.3 --- Characterization of Polymers --- p.39 / Chapter 2.1.4 --- Photophysical Properties of the Polymers --- p.43 / Chapter 2.2 --- Phthalocyanines Substituted with One Poly(norbornene) --- p.49 / Chapter 2.2.1 --- Preparation and Polymerization of Mono(norbornene) Phthalocyanines --- p.49 / Chapter 2.2.2 --- Characterization of the Polymers 41 - 44 --- p.56 / Chapter 2.2.3 --- Fluorescence Quenching of 40 Polymers 41 -44 --- p.61 / Chapter 2.2.4 --- Preparation of Water-soluble Poly(7-oxanorbornene) --- p.63 / Chapter 2.3 --- Conclusion --- p.65 / Chapter 3 --- EXPERIMENTAL SECTION --- p.66 / Chapter 3.1 --- General Methods --- p.66 / Chapter 3.2 --- Photophysical Measurements --- p.67 / Chapter 3.3 --- Synthesis of Phthalocyanines with Four Poly(norbornene) Substituents --- p.68 / Chapter 3.4 --- Synthesis of Phthalocyanines with One Poly(norbornene) Substituent --- p.74 / Chapter 4. --- REFERENCES --- p.77

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Synthesis of novel amphiphilic copolymers based on sugar moieties: development of new architectures and biomedical applications As early as in the 50’s, amphiphilic copolymers started to attract much interest in the frame of polymer science thanks to their self-assemblies as organized nano-structures in a selective solvent. The resulting micelles or vesicles have emerged as potentially useful materials in the biomedical field such as drug delivery systems when matching the specific conditions of size, coating nature and functionalization,… Moreover, active cell-targeting increases the therapeutic effect by selectively delivering the drug to the required cells. Accordingly, carbohydrates have drawn much attention due to the cell recognition processes they can mediate. Carbohydrates are thus incorporated in polymer backbones to mimic the naturally occurring substrate for the adapted cell receptors. The originality of this thesis is based on the use of sugar moieties as potential multi-hydroxylated initiators for the polymerization of various lactones. This leads to well-defined amphiphilic polymer architectures along with the development of a more facile route for the incorporation of carbohydrates in polymer chains to promote active cell-targeting of the as-obtained nano-structures. The first part of the thesis aims at describing the synthesis of novel amphiphilic brush-like polymers via two pathways. A first approach relies upon the synthesis of polyester arms initiated from the alcohol groups of pending sugars distributed along a preformed hydrophilic polymethacrylate backbone obtained by controlled radical polymerization (via ATRP). Various metal-based and organic catalysts/activators have been studied to lead to the desired architectures using this “grafting from” technique. In another synthetic strategy, the lactone polymerization using a carbohydrate initiator has been carried out, followed by end-chain derivatization reactions yielding brush-like copolymers via a “grafting through” technique. Slight modifications of the end-chain functionalities have also afforded the possibility to synthesize amphiphilic mikto-arm copolymers which self-assemble in aqueous medium in micelles characterized by interesting size features affording promising applications as new drug delivery systems. On the other hand this thesis also focuses on the use of carbohydrate moieties in amphiphilic diblock copolymers such as poly(ε-caprolactone)-b-poly(methacrylate-graft-poly(ethylene oxide)-co-6-O-methacryloyl-D-galactopyranose) or poly(ε-caprolactone)-b-poly(methacrylate-graft-poly(ethylene oxide)-co-1-O-methacryloyl-D-mannofuranose), using the combination of lactone ring-opening polymerization with ATRP of the respective functionalized comonomers, followed by selective post-polymerization sugar deprotection. Next to these copolymers based on polylactones and polymethacrylates, fully degradable amphiphilic block copolymers composed of a polycarbonate backbone have been originally designed. To that end, a multi-step procedure involving the synthesis of sugar-substituted cyclic carbonates, block copolymerization reactions and ultimate selective sugar deprotection, has been investigated. The self-organization of the resulting copolymers, e.g., poly(trimethylene carbonate)-b-poly(3-O-(5’-methyl,5’-carboxy-1’,3’-dioxan-2’-one)-D-glucopyranose), has been studied in aqueous medium. Interestingly, the so-formed polymeric micelles proved to display remarkable living cell-targeting properties. Fabian Suriano