Articulated rigid-rod polymers asPBI were synthesized via polycondensation reaction. Using 2-sulfoterephthalic acid and 5-sulfoisophthalic acid in different ratios for copolycondensation reaction making the fully conjugated rigid-rod backbone became articulated. Both rigid-rod and articulated rigid-rod were further derivatized using alkane sulfonated pendants and became water-soluble rigid-rod and articulated rigid-rod polyelectrolytes. Lithium salt doped cast films of the polyelectrolytes showed a root-temperature DC conductivity parallel to film surface (

Polymers in concrete have received considerable attention over the past 30 years. Superplasticizers are one of the admixtures which have polymeric structure. In this study, polycarboxylate type slump-releasing dispersant, which is a copolymer of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and methacrylic acid (MAA), was synthesized in different feed compositions. The synthesis procedure of this copolymer was retrieved from literature. The derivatives of this water-soluble copolymer (AMPS-MAA) were synthesized by a macromonomer which was synthesized by the esterification of poly(ethylene glycol) methyl ether (PEG) with MAA (PEGMA) and then copolymerizing this macromonomer with AMPS monomer, the resulting copolymer is AMPS-PEGMA. In order to study the methyl group effect on fluidity, the other type of macromonomer (PEGA), composed of PEG and acrylic acid (AA), was synthesized and copolymerized with AMPS monomer, giving AMPS-PEGA. The structures of synthesized polymers were verified by NMR and FT-IR analysis. The slump-releasing effect of the synthesized copolymers was studied in terms of reaction pH, composition, molecular weight, amount of PEG side chains, and molecular weight of PEG side chains. The AMPS-MAA copolymer with 40% AMPS content was the most effective in promoting the fluidity of cement pastes. In scope of reaction pH, the AMPS-MAA copolymer, synthesized at a pH of 11, gave the most effective result on fluidity of the cement pastes. In copolymers of PEG acrylate macromonomers and AMPS monomers, copolymers with 5% PEG acrylate content showed the highest fluidity both in copolymers of PEGA and PEGMA. In copolymers with PEG side chains, the 15% AMPS-PEGA copolymer synthesized at pH of 6 gave the most effective result on fluidity of cement pastes. In the study of mechanical properties of the mortar samples prepared by the copolymers selected, AMPS-PEGA copolymer with 25% PEG content showed the highest flexural strength, and AMPS-MAA copolymer with 60% AMPS content and a reaction pH of 11 gave the highest compressive strength. In this study, zeta potential measurements were also performed to analyze the fluidity behavior of the copolymers.

Development of opto-electronic polymers has been focused on conjugated rigid-rod polymers which assume a para-catenated backbone yielding a rod-like configuration. As a consequence of their rigidity, the rod-like molecules display superior mechanical properties, thermo-oxidative stability and solvent resistance. The later two characters cause difficulties in processing these high-performance rigid-rod polymers. This in terms limits their applications in critical technologies, such as conducting polymers, nonlinear optics, and solid polyelectrolytes. In this study, chemical derivatives of the rigid-rod polymers were synthesized using pendants of propane-sulfonated ionomers to (1) enhance the solubility of the rigid-rod polymers, and (2) generate a solid polyelectrolyte suitable for energy storage. Extensive synthesis efforts were focused on generating monomers and polymers of propane-sulfonated poly(p-phenylene-benzobisimidazole), PBI, making it a water soluble electrolyte. Various analysis techniques were applied to ascertain the chemical structure and the purity of the monomers and of the polymers. The polymer molecular weight was also determined using viscometry. An intrinsic viscosity of 4.9 dL/g was achieved for the 2-sulfo-PBI and of 0.58 dL/g for the propane-sulfonated PBI with Na+ ionomer pendants

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Die vorliegende Arbeit beschreibt die Etablierung einer neuen Methode zur Durchführung von Diffusionsmessungen innerhalb weniger Nanometer dicker Polyelektrolytmultischichten. An das Polykation PAH wurde der Fluorophor NBD gekoppelt. PAH-NBD kann im Rahmen des Beschichtungsprozesses an verschiedene Positionen des auf kolloidalen Teilchen adsorbierten PAH/PSS-Multifilms lokalisiert werden. Nach Dithionitzugabe wird die Fluoreszenz durch die ablaufende Reduktionsreaktion zwischen NBD und Dithionit gelöscht. Die Abnahme der Fluoreszenzintensität wird flowzytometrisch detektiert. Die Auswertung der Daten erfolgte auf der Grundlage verschiedener theoretischer Näherungslösungen für Subdiffusion, gekoppelt mit der Reaktionskinetik der Fluoreszenzlöschung. Die Ergebnisse sind nicht mit normaler Diffusion innerhalb der Schichten vereinbar. Vielmehr ergibt sich eine stark subdiffusive Transportcharakteristik des Dithionits innerhalb des Polyelektrolytmultifilms. Als Ursachen hierfür werden die Wechselwirkungen der Dithionitmoleküle mit den PAH-Molekülen sowie die unterschiedlichen Zugänglichkeiten der NBD-Moleküle für die diffundierenden Dithionitmoleküle durch ständige Konformationsänderungen der PAH-Moleküle angesehen. Hervorzuheben ist, dass erstmalig eine Technik etabliert wurde, mit welcher Diffusionsmessungen auf nanoskopischer Skala innerhalb von Polyelektrolytmultischichten durchgeführt werden können. Die subdiffusive Kinetik ist im Vergleich zu normaler Diffusion stark verzögert und ermöglicht dadurch einen länger anhaltenden Stofftransport, was für die Anwendung der Polyelektrolytmultischichten als Medikamententräger besonders vorteilhaft ist. Es wurde gezeigt, dass die Ladung der obersten Schicht des Polyelektrolytmultifilms einen erheblichen Einfluss auf die Qualität und die Struktur der Polyelektrolytmatrix, und das ebenfalls in tieferen Bereichen der Polyelektrolytmultischicht, hat.

La première partie de cette thèse est dédiée à la modification de polyélectrolytes pour former des films de multicouche de polyélectrolytes (PEM) ayant des propriétés d’adhésion de protéine et de cellules bien contrôlées et modifiables par étirement. L’acide polyacrylique a été modifié avec des groupes latéraux phosphorylcholine (PC) à des taux de 25 % (PAA-PC) ou avec des chaînes oligo(éthylène oxyde) terminées par la biotine : (EO)nBiotine (n = 0, 3, 9 et 18) avec de taux de modification de 1, 5, 10 ou 25 %. Des PEM incorporant ces polymères lient spécifiquement la streptavidine et repoussent tout autre protéine. Les propriétés d’adsorption et la sélectivité de ces PEM ont été mesurées par microbalance à quartz. Sur un substrat de PDMS étirables, on a construit des PEM terminés par un PAA portant des RGD recouvert par deux couches contenant PAA-PC. Au repos, seuls les PC sont exposés et inhibent l’adhésion cellulaire ; sous étirement, les groupes RGD sous-jacents sont exposés et déclenchent l’adhésion de fibroblastes.La deuxième partie est consacrée à l‘étude d’acide polyméthacrylique modifié hydrophobiquement avec des chaînes alkyle liées par des esters à la chaîne principale. 3 chaînes différentes ont été greffées : -C12H25 ; -C18H35 et C4H8-OOC- C11H23 avec des taux de 1, 5 and 10 %. Ces polymères sont associatifs et forment des hydrogels dans des tampons physiologiques pour des taux de modifications de 5% et des concentrations supérieures à 4% en poids. Ces gels ont été caractérisés par des mesures rhéologiques. Leur incubation avec des lipases provoque une baisse de leur viscosité, interprétable par une coupure des esters. Quand les gels faits à partir du PAA-C12 sont incubés avec une culture de Pseudomonas aeruginosa, la viscosité baisse également, ce qui montre que les chaînes sont également coupées in vivo. / The first part of this thesis is dedicated to the modification of polyelectrolytes to form polyelectrolyte films with controlled and stretch responsive cell and protein adsorption properties. Poly(acrylic acid) (PAA) was modified with side phosphorylcholine groups (PC) at rates of 25 % or with oligo(ethylene oxide) chains ended by biotin ((EO)nBiotin, (n =0, 3, 9 and 18) at 1, 5, 10 and 25 % modification rates. Polyelectrolytes multilayer films (PEM) containing these polyelectrolytes bind selectively streptavidin but repel all other proteins. The adsorption properties and selectivity were measured by quartz crystal microbalance. On a stretchable PDMS substrate, we have built PEM ended by PAA bearing RGD, covered by two PAA-PC layers on the top. Under rest, only the PC groups are exposed and prevent cell adhesion; when the film is stretched, the underlying RGD groups are exposed, and trigger adhesion of fibroblasts.The second part was consecrated to the study of poly(methacrylic acid) hydrophobically modified with alkyl chains connected through an ester moiety to the main chain. Three different chains were grafted -C12H25; -C18H35 and -C4H8- OOC-C11H23 with a rate of 1, 5 and 10 %. These polymers associate in water and form hydrogels in physiological buffer, for modification rates higher than 5 % and polymer concentrations higher than 4 wt. %. The gels were characterized by rheology. Their incubation with lipases resulted in a decrease of their viscosity, which could be interpreted by the cleavage of the hydrophobic side chains, by rheological tests. When the gels with PAA-C12 were incubated with a culture of Pseudomonas aeruginosa, their viscosity decreased, which shows that alkyle chains are also cleaved in vivo.

La quitina es un biopolímero muy abundante presente en el caparazón de crustáceos, insectos y en la pluma del calamar y la pota, entre otras fuentes. La desacetilación de la quitina forma la quitosana, un polisacárido más versátil por su solubilidad y mayor reactividad química. La quitosana es utilizada en aplicaciones médicas, farmacéuticas, cosméticas, tratamiento de aguas, agricultura e industria alimentaria. / Chitin is an abundant biopolymer that can be found in shells of crustaceans, insects and in squid and pota pen. Deacetylation of chitin produces chitosan, a more versatile polysaccharide due to its solubility and increased chemical reactivity. Chitosan is used in medicine, pharmaceutics, cosmetics, water treatment, agriculture and food industry.

Polypeptides are polymerized chains of amino acids linked covalently through peptide bonds. Polyelectrolyte polypeptides are polypeptides with electrolyte repeating groups. Several amino acids contain ionizable side chains which result in charge distributions when dissolved in aqueous solutions. This dissertation is motivated by a desire to gain knowledge of polyelectrolyte polypeptides as recent advances in chemical synthesis of polypeptides have made possible the fabrication of designed polypeptides that do not naturally occur in nature. Potential applications of newly designed polypeptides span the range from medical to clothing and energy even to robotics. In this dissertation we compare the characteristic behavior of two polypeptide polyanions: Poly-(L-Glutamic Acid) [PLE] and Poly-(L-Glutamic Acid4, Tyrosine1) [PLEY(4:1)]. Comparative characteristic behaviors of each is conducted through relaxation phenomena in the context of mechanical elasticity measurements of hydrogels and dielectric relaxation of aqueous solutions in a radio frequency range of 1 MHz to 1000 MHz. Hydrogels are fabricated by crosslinking each polyanion with Poly-(L-Lysine) [PLK], a polycation, via the crosslinker 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC). Elasticity and viscoelasticity measurements are conducted in a fixture designed by our lab. Dielectric relaxation behavior is studied on aqueous solution of both PLEY and PLE using a capacitive fixture, also designed in our lab. RF signals provided by an impedance analyzer are converted to permittivity and dielectric loss measurements. Peaks in dielectric loss provide evidence of relaxation mechanisms. A comparison of experimental results to theoretical expectations reveal both expected and some surprising behavior. Relaxation times for crosslinked hydro-gels scale according to theoretical expectations according to so-called reptation dynamics. However, relaxation times of aqueous solutions did not scale as entangled polyelectrolytes. First, both PLEY and PLE scaled as neutral polymers rather than polyelectrolytes. This was expected because of the high concentrations studied. However, due to the high concentrations, it was expected that polypeptides were entangled in solutions. Data compared to theory did not support this expectation. We, additionally, conducted a self-crosslinking experiment of a polyampholyte: RADA16. RADA16 is known to self-assemble into nano-fibers formed by -sheet stacking. The self-crosslinking was also mediated by EDC. Results of crosslinking showed formation of polypeptide spherules as well as nano-crystals nominally orthorhombic in shape. It was not possible to ascertain composition of the nano-crystals due to both the limited amount of raw material available and the capabilities of measurement equipment as of this writing. It is hypothesized that nano-crystals are composed of some type of urea by-product from the crosslinking reaction. The spherules, on the other hand, seem to be described by the theory of hydrophobic polyelectrolytes. Additional research conducted with regards to electromagnetic hydrodynamic flows during the time frame of this dissertation is also included. The research uses hydrodynamic conservation equations as a starting point to derive one electromagnetic flow momentum equation analogous to the Cauchy momentum equation of hydrodynamics. It also introduces a mass- energy conservation equation for electromagnetic flow that has no hydrodynamic analogue. We begin this dissertation by introducing in Chapter 1 some of the theoretical background necessary to understand results from experiments. Chapter 2 introduces experimental results from elasticity and viscoelasticity measurements and Chapter 3 explains the dielectric relaxation experiment. We then follow with Chapter 4 which presents conclusions from mechanical and dielectric relaxation experiments in a concise format. Results from the self- crosslinking of RADA16 are presented in Chapter 5. Finally, the additional research on electromagnetic flow is presented in Chapter 6.

This Thesis is devoted to synthesis and characterization of conjugated polymers of three types: (i) copolymers of fluorene-based units with comonomers derived from benzene, anthracene and diphenyloxadiazole; (ii) copolymers combining new thiophene monomers carrying oxadiazole and triazole moieties with various comonomers. Copolymers are designed with the respect to the tuning the optical properties and an improvement in charge transport properties; (iii) polythiophene based polyelectrolytes of two types and the basic characterization of selected physical and optical properties is reported as well as a study of interactions with noble metal nanoparticles. An incorporation of oxadiazole side groups into the fluorene copolymers was followed by the substantial increase in the stability of emission (photoluminescence). Another increase in the emission stability was achieved by the substitution of alkyl side groups on fluorene for the aryl counterparts. Such a change resulted in almost complete suppression of the undesired green emission. Further method was the incorporation of anthracene monomeric units into the main chains which resulted in the best stabilization of emission. An experiment was also made in order to shed some light on the explanation of the mechanism of emission stabilization caused by...