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För att möjliggöra en hållbar utveckling skiftar många polymerforskares fokus just nu från att syntetisera polymerer från fossila resurser till att producera biobaserade polymerer från exempelvis träd. Av särskilt intresse är lignin, som utgör ungefär en tredjedel av allt växtmaterial men i nuläget oftast används som bränsle. Många forskare har undersökt de möjligheter som öppnas genom att bryta ner lignin och modifiera molekylerna som fås därigenom, såsom ferulsyra. Denna studie syftade till att modifiera ferulsyra till en styren-lik monomer med en karboxyl-substituent, och att testa vattenbaserad polymerisation av denna monomer.Det första steget i modifiering var dekarboxylering av ferulsyra. Detta utfördes genom upprepningar av tidigare studier där baskatalyserad dekarboxylering utfördes i polära aprotiska lösningsmedel. Efter flera försök hittades en fungerande metod, där trietylamin gav en dekarboxylering med högt utbyte efter tre timmar i dimetylformamid vid 100 °C. Att isolera produkten var också utmanande i början, men en trestegs-extraktion med H2O och Et2O som avslutades med en tvätt av saltvatten gav tillräcklig renhet. En ättiksyra-grupp adderades till fenolen med hjälp av en tvåstegsreaktion som hittades i litteraturen, men inte förrän ett dussin försök till nya metoder med kloroättiksyra gjorts utan framgång. I den fungerande metoden tillsattes en acetatgrupp med metylbromoacetat i återkokande aceton med kaliumkarbonat som bas, innan acetatet demetylerades av litiumhydroxid i en metanol/vattenblandning vid rumstemperatur.Den resulterande monomeren, 4-oxy-ättiksyra-3-methoxy-styren (OAMS), sampolymeriserades med styren, både i bulk- och emulsionspolymerisation. Bulksampolymeren hade en något högre molekylvikt och glastransitionstemperatur än homopolystyren, med en betydligt högre dispersitet. Emulsionspolymerisation var utmanande, eftersom OAMS inte är särskilt löslig i vare sig vatten eller styren, och i slutändan producerades inga tydliga resultat genom dessa försök.  Studiens huvudsakliga slutsats är att även om det är möjligt att syntetisera ren OAMS från ferulsyra, är användbarheten av denna molekyl som monomer i vattenbaserad polymerisering inte övertygande, eftersom den är så pass olöslig om inte bas tillsätts, vilket introducerar risken för hydrolys.Slutligen, även om studien ledde till få säkra slutsatser på grund av flera ofullständiga resultat, uppnåddes huvudsyftet att modifiera ferulsyra och testa polymerisation av den bildade monomeren. / To enable a sustainable development, scientific focus is shifting from synthesizing polymers from fossil-based resources to producing bio-based polymers from for example wood. Of particular interest is lignin, which makes up about a third of plant matter but is nowadays most commonly used as fuel. A great deal of research has explored the possibilities opened up by breaking down lignin and modifying its derived molecules, such as ferulic acid. This study aimed to modify ferulic acid into a styrenic monomer with an acidic substituent, and to investigate the aqueous polymerization of this monomer.The first step of modification was the decarboxylation of ferulic acid. This was attempted through recreations of previous studies where base-catalysed decarboxylation was carried out in aprotic polar solvents. After several trials, a successful procedure was found, where triethylamine gave a high-yield decarboxylation after three hours in dimethylformamide at 100 °C. Isolating the product was also initially challenging, but a three-step extraction with H2O and Et2O finished by a wash of brine gave sufficient purity.Adding an acetic acid-group to the phenol was achieved using a two-step procedure found in literature, but not before trying a dozen novel methods using chloroacetic acid without success. In the working procedure, an acetate group was added using methyl bromoacetate in refluxed acetone with potassium carbonate as base, before demethylating the acetate using lithium hydroxide in a methanol/water mix at room temperature. The resulting monomer, 4-oxy-acetic acid-3-methoxy-styrene (OAMS), was copolymerized with styrene, both in bulk and emulsion radical polymerization. The bulk copolymer displayed a slightly higher molecular weight and glass transition temperature than homopolystyrene, with a significantly higher dispersity. Emulsion polymerization was challenging, as OAMS is not very soluble in either water or styrene, and ultimately, no conclusive results were produced through this route.The study concluded that while it is possible to synthesize pure OAMS from ferulic acid, the degree of usability of this molecule as a monomer in aqueous polymerization is not certain, as it is hardly soluble without the addition of base, which introduces the risk of hydrolysis. Ultimately, although few solid conclusions could be drawn from this study due to several incomplete results, the core objective of modifying ferulic acid and testing polymerization of the resulting monomer was achieved.

Herein, we present a quasi-living Negishi-type catalyst-transfer polycondensation of a zinc–organic DTSbased monomer which provides an access to narrowly distributed poly(4,4-bis(2-ethylhexyl)dithieno[3,2-b:20,30-d]silole (PDTS) with controlled molecular weight. The synthesis of well-defined all-conjugated diblock copolymers containing a PDTS block was accomplished by a combination of Kumada and Negishi catalyst-transfer polycondensations (KCTP and NCTP, respectively). Particularly, it was shown that living P3HT chains obtained by KCTP of magnesium–organic thiophene-based monomer efficiently initiate NCTP of zinc–organic DTS-based monomer. The purity of the DTS-based monomer was found to be a crucial factor for achieving a clean chain-growth polymerization process. A combination of physico-chemical methods was used to prove the success of the block copolymerization.

Current FDA approved anti-cytomegalovirus antivirals are ganciclovir, foscarnet, and cidofovir. These drugs target the viral polymerase to inhibit DNA synthesis. Halogenated benzimidazoles target a step later in viral replication during packaging and cleavage of the viral genome. The compounds 2-Bromo-5,6-dichloro-1-(β-D-ribofuranosyl)benzimidazole (BDCRB) and 2,5,6-trichloro-1-(β-D-ribofuranosyl)benzimidazole (TCRB) are novel inhibitors of human cytomegalovirus (HCMV) and resistance to these compounds are found within the human cytomegalovirus viral terminase. Terminase is unique to the virus and in theory provides a good target for antiviral development. Beginning with a BDCRB resistant guinea pig cytomegalovirus observations found a single mutation located in the viral terminase gene UL89 and unique formation found in genomic ends. In guinea pigs, the virus continued to produce large amounts of monomer. This is in contrast to human cytomegalovirus treated with either BDCRB or TCRB. Both compounds produced very little monomer DNA but created a supergenomic species, called monomer-plus that migrates to the apparent size of 270-kb on a pulse field gel. A model was developed to explain formation of monomer plus and my project aims originated from the model. In the presence of BDCRB and TCRB, packaging is relaxed resulting in the normal cleavage site being skipped and cleavage occurring at the next available cleavage site creating a short-long-short genome. In guinea pigs, cleavage has been relaxed by premature cleavage of the terminal ends. Current antivirals do not block viral entry therefore, patients are infected with HCMV. Blocking entry of HCMV into cells would prevent HCMV infection. It has been shown that antibodies to epitopes within the gH/gL/UL128-131 complex can block viral entry into endothelial, epithelial, and other cell types while antibodies to gB block entry into fibroblasts. The majority of the current work on entry into epithelial cells has been performed in retinal pigment epithelium and epithelial cells derived from tumors. Viral entry into cell lines derived from mucosa cells was dependent on the complex gH/gL/UL128-131. Rabbit antibodies raised against UL130 and UL131 peptides neutralized epithelial entry with effects as potent as human seropositive sera. This suggests that the entry complex can be blocked by single epitopes.

A técnica de polimerização em emulsão tem sido usada cada vez mais na indústria de tintas, resinas, plásticos, entre outros. Esse crescimento se deve as razões ambientais (uma vez que se utiliza água como fase contínua desta reação), também a versatilidade e a capacidade de produzir látex com diferentes propriedades para diferentes aplicações. Polímeros em emulsão são produtos por processo, isto é, suas propriedades são definidas durante a polimerização. Por isso, é importante o adequado monitoramento da reação de modo a permitir o controle das propriedades desejadas. A técnica de espectroscopia na região do infravermelho próximo (NIR), combinada com o uso de fibras óticas, é muito promissora para o monitoramento multivariável, em linha e em tempo real do processo de polimerização. O objetivo deste trabalho foi o de estudar o uso de espectroscopia NIR para o monitoramento em linha e em tempo real das concentrações de monômero e de não- voláteis (conhecido também como teor de sólidos) e da evolução do tamanho médio das partículas de látex (Dp) durante a reação de polimerização em emulsão de metacrilato de metila (MMA), em escala de laboratório e processo semi-batelada. Os modelos de calibração para estas variáveis foram obtidos experimentalmente empregando o método de regressão por mínimos quadrados parciais, PLS. Os resultados obtidos confirmaram algumas regiões espectrais do NIR indicadas em literatura como sendo adequadas na predição de monômero e Dp e revelaram -1 comportamentos espectrais ainda não explicados na região entre 10.475 e 13.000 cm , relacionados às variações no tamanho das partículas. Os resultados mostram também que é possível monitorar em linha e em tempo real a evolução do Dp e dos teores de monômero (MMA) e de não voláteis, simultaneamente em um único instrumento, utilizando modelos de calibração com bandas espectrais e pré-tratamentos distintos. / Emulsion polymerization is a largely and increasingly used technique in industrial production of paints, resins, plastics among others. This increase is due to environmental reasons (since water, rather than organic solvents is used as dispersing medium), as well as to the versatility and capacity of producing products with different properties for different applications. Emulsion polymers are products by process, i.e., the properties are mainly defined during the polymerization process. Thus, the adequate process monitoring is important for achieving the target properties. The NIR spectroscopy combined with optical fibers is a promising technique for the task of multivariable, real-time, in-line monitoring of polymerization processes. The aim of this work is the study of use of NIR spectroscopy for in-line, real time monitoring of the monomer and solids content, as well as the evolution of average size of the polymer particles (Dp), during semi-batch emulsion polymerization of methyl methacrylate in laboratory reactor. The calibration models for each of the monitored variables were obtained by applying the partial least squares regression method (PLS). The results confirmed that some NIR spectral ranges recommended in the literature are appropriate for the prediction of monomer content and Dp, and that there are spectral -1 . The results behaviors not yet explained in the region between 10475 and 13000cm also show that the in-line, the changes in Dp, monomer and polymer content can be simultaneously monitored in-line and in real time by NIR spectroscopy by using calibration models based on adequate spectral regions and distinct data pretreatments.

O objetivo deste trabalho foi o de avaliar a resistência à flexão e a quantidade de monômero residual superficial em resinas acrílicas para bases de próteses totais. Para tanto foram confeccionados corpos-de-prova nas dimensões de 2.5mm x 10mm x 65mm, utilizados em ambas as análises. Padronizou-se o processo de inclusão no qual foram empregadas muflas plásticas reforçadas por fibras de vidro. Sete grupos foram constituídos, de acordo com o tipo de processamento empregado na polimerização das resinas: Ac (Acron-MC) e Vw (Vipi-Wave) de ativação por energia de microondas; Lt (Lucitone 550 – grupo controle) e Vc (Vipi-Cril), resinas de ativação térmica convencional em banho de água aquecida no ciclo longo; Qc (QC-20), uma resina de ativação térmica em ciclo rápido e, dois grupos cuja resina era a mesma de ativação química (Vipi-Flash), processada em duas condições – à temperatura ambiente (Vf1) e, por aquecimento adicional em banho de água (Vf2). Os resultados mostraram diferenças estatisticamente significantes, onde o grupo Ac obteve as maiores médias para resistência flexural e os menores níveis de monômero liberado em relação às demais resinas. Os grupos Qc e Vf1 evidenciaram os piores resultados para ambos os testes, e a princípio, pareceu haver uma relação de causa e efeito entre, os elevados níveis de monômero residual encontrado nestes grupos, e a baixa resistência flexural observada. Verificou-se ainda que a imersão em água aquecida por 30min, da resina de ativação química, propiciou um ganho em qualidade do material para as características avaliadas. / The purpose of this work was the evaluation of flexural strength and quantity of superficial residual monomer in acrylic resin for complete denture. To perform both analyses it was developed specimens with a dimension of 2.5mm x 10mm x 65mm. The inclusion process was standardized by the use of plastic flasks reinforced with fiberglass. Seven groups were constituted in accordance with the type of resin polymerization process: Ac (Acron-MC) and Vw (Vipi-Wave) activated by microwave energy; Lt (Lucitone 550 – control group) and Vc (Vipi-Cril), conventional water bath curing cycles of heat activated acrylic resin; Qc (QC-20), fast cycle thermal activation; and two groups of self cured resin (Vipi-Flash), processed in two distinguished conditions: ambient temperature (Vf1) and additional heating in water bath (Vf2). The results have shown statistical significant differences. The Ac group had the highest mean to flexural resistance and the least level of released monomer in comparison with others resins. The Qc and Vf1 groups had the worst results for both tests. The initial conclusions showed a cause-effect relation between higher levels of residual monomer and lower flexural strength to this group. Additionally, it was verified that the immersion for 30 minutes of self cured resin in heated water gave an improvement of material quality to evaluated characteristics.

Cette thèse a pour but la synthèse de nouveaux polymères par polymérisation anionique et organo-catalyse de polymérisation par activation du monomère. Ce sujet s’articule autour de deux axes majeurs : 1) La synthèse de nouveaux polyamides par activation d’amines aromatiques ou de dérivés acrylamides 2) L’étude de l’ouverture de cycle d’aziridines activées catalysée par les carbènes N-heterocycliques. Le but de cette thèse est donc d’étudier les mécanismes mis en jeu lors de ces polymérisations. Les polymères obtenus seront caractérisés par les méthodes d’analyses classiques (RMN, chromatographie par exclusion stérique, analyses thermiques, spectrométrie de masse, etc.) / In this thesis, the ring-opening polymerization by a monomer activation strategy of heterocyclic monomers such as lactams and aziridines was investigated. In the first part, we described that covalently activated aziridines, i.e. N-sulfonyl aziridines, could be subjected to the N-heterocyclic carbene organocatalyzed ring-opening polymerization (NHC-OROP) in a living/controlled manner. Secondary activated amine, non-activated secondary amine as well as functional initiators were used to promote the ring-opening polymerization of N-activated aziridines. The high tolerance to various chemical functions and the high level of control of the so-called NHC-OROP have allowed the synthesis of well-defined and original aziridine-based block copolymers. On the other hand, the simultaneous combination of anionic ring-opening of ε-caprolactam and condensation reactions of aminobenzoate derivatives was shown to occur in a « one-step » bulk copolymerization allowing the preparation of aliphatic-aromatic copolyamides with enhanced thermal properties (including the glass transition temperature). Alternatively, other methodologies such as covalent activation of lactams with electron withdrawing group or the hydrogen transfer polymerization of acrylamide derivatives were investigated for the synthesis of new polyamides.

In order to achieve a more stable and highly proton conducting membrane that is also cost effective, the perfluoroalkyl benzenesulfonylimides (PFSI) polymers are proposed as electrolyte for Proton Exchange Membrane Fuel Cells. 4-(trifluoromethyl)-2-diazonium perfluoro-3, 6-dioxa-4-methyl-7-octene benzenesulfonyl imide (I) is synthesized from Nafion monomer via a 5-step schematic reaction at optimal reaction conditions. This diazonium PFSI zwitterionic monomer can be further subjected to polymerization. The loss of the diazonium N2+ functional group in the monomer is believed to form the covalent bond between the PFSI polymer electrolyte and carbon electrodes support. All the intermediates and final products were characterized using 1H NMR, 19F NMR and IR spectrometry.

By using the technology of molecularly imprinted polymer (MIP), we propose to synthesize a protein conformational imprint that also acts as a plastic enzyme, inducing protein structural transitions. The imprint aims at MIP-induced stabilization and / or formation of bound protein secondary structure and the applications associated with analysis and correction of misfolded proteins. The screening of polymeric functional monomers being able to induce the conformational transitions in proteins is investigated in this report. The fluoro-silanes (3-heptafluoroisopropoxy)propalethoxysilane (7F) and 3,3,3-trifluoropropylmethoxysilane (3F) were employed as functional monomers for synthesis of this catalytic protein conformational imprint via sol-gel reactions. 3F was demonstrated superior to 7F for fluoro-modification of tetraethylorthosilicate (TEOS) gel in terms of retaining gel transparency and increasing hydrophobicity while maintaining a uniform distribution of encapsulated protein. Both hydrolyzed 3F and polymerized 3F exhibited strong influences on structure transitions of three template proteins: bovine serum albumin (BSA), beta-lactoglobulin (BLG), and bovine carbonic anhydrase (BCA). The formation of molten globule intermediates that stabilized by increased alpha-helices was induced by the trifluoro-silane in BLG and BCA. Additionally, 3F was effective at a lower concentration than the benchmark fluoro-alcohol 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), validating the application of 3F as a functional monomer for protein conformational imprinting.