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1
Ali, Mir Mukkaram Stöver Harald D. H. "Polymer capsules by living radical polymerization /." *McMaster only, 2004.
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2
Terashima, Takaya. "Multifunctional designer catalysts via living radical polymerization." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136272.
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Iida, Kazunori. "Organotellurium and organostibine mediated living radical polymerization." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144038.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第12354号<br>工博第2683号<br>新制||工||1379(附属図書館)<br>24190<br>UT51-2006-J346<br>京都大学大学院工学研究科合成・生物化学専攻<br>(主査)教授 吉田 潤一, 教授 澤本 光男, 教授 大嶌 幸一郎<br>学位規則第4条第1項該当
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Fujimura, Kojiro. "“Concerted Redox” Catalysis in Living Radical Polymerization." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215571.
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Xie, Min. "Nitroxide-mediated living radical styrene polymerization in miniemulsion." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0020/MQ54494.pdf.
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Yoshikawa, Chiaki. "Fundamental and applied studies on living radical polymerization." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144033.
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Kotani, Yuzo. "LIVING RADICAL POLYMERIZATION OF STYRENE BY TRANSITION METAL CATALYSTS." Kyoto University, 2000. http://hdl.handle.net/2433/180982.
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Aran, Bengi. "Polymerization And Characterization Of Methylmethacrylate By Atom Transfer Radical Polymerization." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605042/index.pdf.
Testo completoAbstract (sommario):
In this work, methylmethacrylate, MMA was polymerized by ATRP method to obtain low molecular weight living polymers. The initiator was p-toluenesulfonylchloride and catalyst ligand complex system were CuCl-4,4&rsquo<br>dimethyl 2,2&rsquo<br>bipyridine. Polymers with controlled molecular weight were obtained.
The polymer chains were shown by NMR investigation to be mostly syndiotactic. The molecular weight and molecular weight distribution of some
polymer samples were measured by GPC method. The K and a constants in [h]=K Ma equation were measured as 9.13x10-5 and 0.74, respectively. FT-IR and X-Ray results showed regularity in polymer chains. The molecular weight-Tg relations were verified from results of molecular weight-DSC results.
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Ando, Tsuyoshi. "DESIGN AND MECHANISM OF TRANSITION METAL-MEDIATED LIVING RADICAL POLYMERIZATION." Kyoto University, 2000. http://hdl.handle.net/2433/180981.
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Simms, Ryan W. "Living/controlled Polymerization Conducted in Aqueous Based Systems." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/700.
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Nishizawa, Keita. "Environmentally Benign Metal-Catalyzed Living Radical Polymerization：Polymerization in Water and Iron Catalysis." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215960.
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Koh, Kyoungmoo. "Precision design of organic/inorganic hybrid materials by living radical polymerization." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144932.
Testo completoAbstract (sommario):
Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第11588号<br>工博第2534号<br>新制||工||1344(附属図書館)<br>23231<br>UT51-2005-D337<br>京都大学大学院工学研究科高分子化学専攻<br>(主査)教授 福田 猛, 教授 伊藤 紳三郎, 教授 金谷 利治<br>学位規則第4条第1項該当
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Zwaneveld, Nikolas Anton Amadeus Chemical Engineering & Industrial Chemistry UNSW. "Surface grafting of polymers via living radical polymerization techniques; polymeric supports for combinatorial chemistry." Awarded by:University of New South Wales. Chemical Engineering and Industrial Chemistry, 2006. http://handle.unsw.edu.au/1959.4/33361.
Testo completoAbstract (sommario):
The use of living radical polymerization methods has shown significant potential to control grafting of polymers from inert polymeric substrates. The objective of this thesis is to create advanced substrates for use in combinatorial chemistry applications through the use of g-radiation as a radical source, and the use of RAFT, ATRP and RATRP living radical techniques to control grafting polymerization. The substrates grafted were polypropylene SynPhase lanterns from Mimotopes and are intended to be used as supports for combinatorial chemistry. ATRP was used to graft polymers to SynPhase lanterns using a technique where the lantern was functionalized by exposing the lanterns to gamma-radiation from a 60Co radiation source in the presence of carbon tetra-bromide, producing short chain polystyrene tethered bromine atoms, and also with CBr4 directly functionalizing the surface. Styrene was then grafted off these lanterns using ATRP. MMA was graft to the surface of SynPhase lanterns, using g-radiation initiated RATRP at room temperature. It was found that the addition of the thermal initiator, AIBN, successfully increased the concentration of radicals to a level where we could achieve proper control of the polymerization. RAFT was used to successfully control the grafting of styrene, acrylic acid and N,N???-dimethylacrylamide to polypropylene SynPhase Lanterns via a -initiated RAFT agent mediated free radical polymerization process using cumyl phenyldithioacetate and cumyl dithiobenzoate RAFT agents. Amphiphilic brush copolymers were produced with a novel combined RAFT and ATRP system. Polystyrene-co-poly(vinylbenzyl chloride) created using gamma-radiation and controlled with the RAFT agent PEPDA was used as a backbone. The VBC moieties were then used as initiator sites for the ATRP grafting of t-BA to give a P(t-BA) brush that was then hydrolyzed to produce a PAA brush polymer. FMOC loading tests were conducted on all these lanterns to assess their effectiveness as combinatorial chemistry supports. It was found that the loading could be controlled by adjusting the graft ratio of the lanterns and had a comparable loading to those commercially produced by Mimotopes.
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Paeth, Matthew S. "Copper Catalysis: Perfluoroalkylation and Atom Transfer Radical Polymerization." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1632226983121513.
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Elkins, Casey Lynn. "Living Polymerization for the Introduction of Tailored Hydrogen Bonding." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/28008.
Testo completoAbstract (sommario):
In an effort to synthesize macromolecules comprising both covalent and non-covalent bonding to tune ultimate physical properties, a variety of methodologies and functionalization strategies were employed. First, protected functional initiation, namely 3-[(N-benzyl-N-methyl)amino]-1-propyllithium and 3-(t-butyldimethylsilyloxy)-1-propyllithium, in living anionic polymerization of isoprene was used to yield well-defined chain end functional macromolecules. Using both initiating systems, polymers with good molar mass control and narrow molar mass distributions were obtained and well-defined chain end functionality was observed. There was no observed effect on the polymer microstructure from the polar functionality in the initiator, with ~92% 1,4- and 8% 3,4-enchainment observed in each case. Further investigation of the 3-[(N-benzyl-N-methyl)amino]-1-propyllithium initiated polyisoprenes proved that facile deprotection was not possible and residual catalyst was not removable from the polymer. However, polymers initiated with 3-(t-butyldimethylsilyloxy)-1-propyllithium were quantitatively hydrogenated and deprotected under relatively mild conditions to yield hydroxyl functional macromolecules in several architectures, including linear and star-shaped. Excellent conversion from arm polymer to star polymer was observed and well-defined macromolecules were obtained. Subsequently, a series of non-functional, hydroxyl functional, and 2-ureido-4[1H]-pyrimidone (UPy) chain end functional linear and star-shaped poly(ethylene-co-propylene)s were synthesized and characterized. The melt phase properties were investigated using melt rheology and the effect of macromolecular topology and multiple hydrogen bond functionality was investigated. Linear UPy functional poly(ethylene-co-propylene)s exhibited increased viscosity and shear thinning onset at lower frequencies than non-functional polymers of similar molar mass due to interaction of the multiple hydrogen bonding groups. Star-shaped UPy functional poly(ethylene-co-propylene)s showed inhibition to terminal flow and the absence of a zero shear viscosity in melt rheological characterization, indicative of a network like structure imparted from the multiple hydrogen bonding interactions.
In addition, the living anionic polymerization of D3 was controlled using the functionalized initiators 3-[(N-benzyl-N-methyl)amino]-1-propyllithium and 3-(t-butyldimethylsilyloxy)-1-propyllithium. Good molar mass control and narrow molar mass distributions were observed. In contrast to the polyisoprene homopolymers, facile deprotection of the 3-(t-butyldimethylsilyloxy)-1-propyllithium was not possible due to the acid sensitivity of the poly(dimethylsiloxane) backbone. However, facile deprotection of the protected secondary amine was achieved through hydrogenolysis and well-defined terminal amine functionalized poly(dimethylsiloxane) was synthesized, which are then amenable to further functionalization reactions.
In contrast to the well-defined polymers synthesized using living anionic polymerization, free radical polymerizations was used to synthesize free radical copolymers with broader polydispersities and pendant UPy groups. These copolymers were compared with a simple dimeric hydrogen bonding carboxylic acid containing copolymer. Melt rheological characterization revealed that, at similar concentrations, the effect of the UPy group was much greater than the carboxylic acid, and broadened plateau moduli and increased viscosity for the UPy containing polymers were observed, while the acid containing polymer exhibited similar results to a non-functional control. The dynamic viscosity was observed to increase systematically with increasing UPyMA incorporation and the quadruple hydrogen bonding interactions were observed to dissociate between ~80-150 °C.<br>Ph. D.
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Çakir, Pinar. "Molecularly imprinted polymer nanostructures by controlled / living radical polymerization with multi-iniferters." Compiègne, 2012. http://www.theses.fr/2012COMP2018.
Testo completoAbstract (sommario):
Les polymères à empreintes moléculaires (MIPs) sont des matériaux synthétiques contenant des cavités capables de reconnaître spécifiquement une molécule cible. Ils se présentent comme une alternative intéressante face aux anticorps biologiques en raison de leur meilleure stabilité chimique et physique, leur meilleure disponibilité et leur moindre coût. Traditionnellement, les MIPs sont synthétisés par polymérisation de monolithes, qui sont ensuite broyés mécaniquement, engendrant des particules de taille micrométrique et de formes irrégulières. Durant ces dernières années, de nombreuses techniques de polymérisation ont été développées afin d’obtenir des particules MIP sphériques de tailles micro et nanométriques, et plus particulièrement des nanogels quasi-solubles. Dans l’optique d’une application en biologie, des tailles de quelques nanomètres - de l’ordre de grandeur de la taille des protéines – sont souhaitées, ce qui pose un réel défi pour leur synthèse, car la faible densité du matériau (une particule ne consiste que de quelques chaines de polymère) s'oppose à l'impression d'une mémoire moléculaire. Nous avons développé une nouvelle approche de synthèse de MIP nanogels dont la taille est proche de celle des anticorps naturels. Notre stratégie est basée sur l’utilisation d’un nouveau type d'amorceur pour la polymérisation radicalaire contrôlée comprenant des fonctions iniferter multiples attachées à un noyau dendritique. Cela permet de générer une concentration localement élevée de radicaux et ainsi, d'obtenir des nanogels de polymère dont la densité est augmentée. Ces travaux de thèse ont conduit à l’obtention des nanogels de MIP de 17 nm de diamètre avec un effet impression appréciable, une bonne affinité pour la cible, le beta-antagoniste propranolol, et une sélectivité moléculaire prononcée. En plus de la synthèse des nanogels solubles de MIP, des motifs de MIP micro et nanostructurés ont été greffés sur des surfaces planes de silicium. Le multiiniferter a été imprimé à la surface par lithographie douce, et fixé chimiquement par son groupement carboxyle central. Les MIPs ont ensuite été synthétisés par une approche « bottom up », caractérisés par spectroscopie d'émission optique, la spectroscopie Raman et la microscopie à force atomique, et la reconnaissance moléculaire de la cible a été visualisée par microscopie de fluorescence. Ces nouveaux matériaux, nanogels et surfaces imprimées offrent de nombreuses perspectives pour la détection par biocapteurs et biopuces, en particulier dans le domaine du biomédical<br>Molecularly imprinted polymers (MIPs) are synthetic materials with specific recognition properties for target molecules. They are considered an alternative to antibodies and are characterized by a higher chemical and physical stability, better availability and lower cost. Historically, MIPs were synthesized as bulk monoliths that were subsequently broken down mechanically in order to form particles of a size in the micrometer range, with irregular shapes. During the last decade, research has focused on the direct synthesis of spherical MIP micro and nanoparticles, and, more recently, on protein-sized, quasi-soluble MIP nanogels in order to widen the application range of MIPs in the biological field. The main difficulty of synthesizing MIPs with diameters in the low nm region is the low density of the resulting polymer network consisting only of a few polymer chains, which makes it difficult to imprint and maintain a molecular memory. In this thesis, we propose an original approach to the synthesis of quasisoluble MIP nanogels with a size in the low nm range, close to that of real antibodies. The proposed procedure involves a new type of initiator for controlled/living radical polymerization, based on multiple iniferter moieties attached to a dendritic core. This allows for the generation of a higher local radical density, and thus for the synthesis of denser nanogels. By using this strategy, MIP Nanogels of 17 nm size with an appreciable molecular imprinting effect, a good affinity for the target molecule, the chiral drug propranolol, and a good selectivity were obtained. In addition, these multiiniferters were also used for the bottom-up synthesis of thin MIP patterns on silicon wafers, by surface-initiated polymerization. The multi-iniferter was printed on to the surface by soft lithography and chemically attached through its carboxyl-functionalized core, followed by the in-situ synthesis of the MIP. Well defined MIP patterns were obtained, which were characterized by optical emission spectroscopy, Raman spectroscopy, atomic force microscopy, and the specific binding of the target molecule was visualized by fluorescence microscopy. We believe that the synthesis, in solution and at surfaces, of protein-size MIP nanogels with specific recognition properties will provide new opportunities for biosensors and biochips technologies in biomedical applications
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Ishio, Muneki. "Design of Active and Versatile Iron(II) Catalysts for Living Radical Polymerization." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120892.
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Ejaz, Muhammad. "Controlled Surface Grafting of Well-Defined Polymers by Living Radical Polymerization Techniques." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/150698.
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Krivorotova, Tatjana. "Synthesis of polyelectrolytes contaiting poly(ethylene oxide) side chains by living radical polymerization." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100915_162344-10990.
Testo completoAbstract (sommario):
The main goal of this work was to synthesize polyelectrolyte brushes containing poly(ethylene oxide) side chains by living polymerization. Brush-like macromolecules are unique polymer molecules whose conformation and physical properties are controlled by steric repulsion of densely grafted side chains. Molecules can be either flexible or stiff, depending on the grafting density and the length of the side chains. Polymerization of macromonomers is one of the most useful ways to prepare brush copolymers. However, with the macromonomer method, the distribution of the spacing of the side chains cannot be entirely controlled which along with broad and multimodal molecular weight distribution makes these polymers heterogeneous. These problems were considered to be overcome with the use of controlled/living polymerization.
Conventional free-radical and RAFT copolymerization of poly(ethylene oxide) substituent containing methacrylate macromonomers, PEO5MEMA and PEO45MEMA, with methacrylic acid (MAA) was studied by the use of 1H NMR spectroscopy for an analysis of residual monomers. RAFT copolymerization of PEO45MEMA and MAA enabled to synthesize comb copolymers with low composition distribution and more homogeneous distribution of PEO side chains along the mainchain. Amphiphilic non-ionic blockcopolymers poly(lauryl methacrylate) (PLMA) – P(PEOnMEMA) and amphiphilic anionic blockcopolymers PLMA – PMAA were prepared by the RAFT method, and their properties in aqueous and THF... [to full text]<br>Vienas iš šiuolaikinės polimerų chemijos uždavinių – gauti numatytos molekulinės masės ir architektūros polimerines medžiagas. Neseniai buvo sukurti nauji radikalinės polimerizacijos metodai, kurie priskiriami gyvybingajai (valdomai) polimerizacijai (GRP). Makromonomerų (MM) gyvybingoji radikalinė polimerizacija yra efektyvus būdas gauti šepetinius (cilindrinius) polimerus). Šepetiniai polimerai – tai makromolekulės, kuriose prie pagrindinės polimerinės grandinės prijungta daug šoninių mažesnės molekulinės masės polimerinių (oligomerinių) grandinių. Dėl tarp šoninių grandinių esančių erdvinės stūmos jėgų tokios makromolekulės įgauna neįprastų savybių, pvz., standumą, cilindrinę formą, didelį segmentų tankį.
Pagrindinis šio darbo tikslas buvo susintetinti norimos sudėties šepetinius polielektrolitinius polimerus, sudarytus iš krūvį turinčios poli(met)akrilato pagrindinės grandinės ir šoninių polietilenoksido grandinių, ir ištirti jų savybes.
Svarbiausieji šio darbo rezultatai, atspindintys jo naujumą, originalumą ir svarbą:
Pirmą kartą nuodugniai ištirta metakrilo rūgšties (MAR) ir dviejų skirtingų molekulinių masių polietilenoksido metakrilatų PEOnMEMA (n = 5, 45) kopolimerizacija įprastiniu radikaliniu ir RAFT metodais. Sukurta metodika PEO makromonomerų kopolimerizacijos kinetikai tirti, užrašant 1H BMR spektrus in situ ir įvertinant likutinę monomerų koncentraciją reakcijos mišinyje bei momentinę kopolimero sudėtį iki gilių konversijų. Netiesiniu kintamųjų paklaidų metodu... [toliau žr. visą tekstą]
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Skene, William G. "Investigation of nitroxide-mediated thermal and photochemical reactions of living free radical polymerization." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6351.
Testo completoAbstract (sommario):
The work presented in this thesis deals primarily with living free radical polymerization (LFRP). Two main specific areas of this process have been studied; thermal and photochemical reaction sequences. Stoichiometric unimolecular initiators were found to be ideal probes for studying the reactions involved in the LFRP process. The bond dissociation energy (BDE) of the labile C-O bond of the alkoxyamine initiators was found to be ca. 28 kcal/mol and is dependent on the resulting carbon centered radical produced upon thermal decomposition. Lower activation energies were measured for more stable carbon centered radicals. Complementary to the thermal studies, photoacoustic studies (PAC) involving photochemical decomposition of the initiators led to the homolytic N-O and C-O bond cleavages in addition to disproportionation product formation. The BDE for the N-O bond of these initiators is ca. 43 kcal/mol. These studies also provided insight into volume effects, where a strict homologous solvent series is not required for extrapolating true enthalpies of reactions and volume correction factors for PAC. The decomposition quantum yields of a series of ketone based actinometers used for PAC BDE studies were re-evaluated and found to be solvent independent. The specific kinetics of thermal LFRP were equally investigated through the use of probes which are normally used for thermal initiation. Fast time resolved techniques of laser flash photolysis (LFP) were used to measure the bi-molecular rate constant for the coupling reaction between a carbon centered radical and a nitroxide radical involved in LFRP. Typical values lay in the area of 108 M-1 s-1 and are influenced by the structure of the carbon centered radical and not that of the nitroxide. The rate constants were observed to be slower with more stable carbon centered radicals, similar to the BDE results where weaker dissociation energies were observed. The formation of minor disproportionation products upon thermal decomposition of the unimolecular initiators was assigned to a concerted four center elimination ultimately responsible for the lack of controlled polymerization with acrylates. The incorporation of steric effects into the monomer or the nitroxide suppressed the formation of these products by increasing the energy barrier necessary for correct orbital alignment required for the elimination reaction. Living polymerization of acrylate monomers was achieved with a nitroxide containing bulky substituents in its 2 and 6 positions. Moderate success of living polymerization was also achieved with acrylate type monomers through the use of an additional phase not miscible with the bulk phase. Chromophores producing triplet states upon excitation were found to undergo fast and efficient energy transfer to a covalently linked alkoxyamine subsequently promoting C-O bond homolysis. The orientation of the C-O bond relative to the chromophore in addition to the distance separating the two influences the efficiency of energy transfer and bond cleavage. Using a benzophenone type chromophore with a covalently linked alkoxyamine initiator promoted photoinduced living type polymerization of acrylate.
21
Bompart, Marc. "Molecularly imprinted polymers and nano-composites by free radical and controlled/living radical polymerization : applications in optical sensors." Compiègne, 2010. http://www.theses.fr/2010COMP1870.
Testo completoAbstract (sommario):
Cette thèse est organisée en trois chapitres basés sur trois publications et deux manuscrits en cours de soumission. Les polymères à empreintes moléculaires (MIP) sont des récepteurs produits à façon qui sont obtenues par polymérisation en présence de molécules modèles. Le premier papier décrit l'utilisation de la spectroscopie Raman pour la détection et la quantification de molécules modèles au sein d'une particule unique de polymères a empreintes moléculaires de taille micrométrique. Les particules de polymères ont eté imprimées avec comme molécules modèles S-propranolol. Des particules de taille nanométrique et micrométrique ont été respectivement utilisées pour une analyse en masse et sur particule unique. La quantification de molécules cibles est possible sur particule unique et une limite de détection de 1µM a été obtenue sur l’analyse en masse. Le second papier décrit un capteur chimique de taille nanométrique composé d’une particule en core-shell composite. Cette particule comprend un cœur polymérique, une enveloppe inorganique composée de nanoparticules d’or pour l’exaltation du signal, recouvert d’une couche de polymères à empreintes moléculaires pour la reconnaissance. La méthode d’analyse utilisée est une exaltation su signal Raman appelé « surface enchanced Rama scattering ». Ces particules ont aussi été utilisées comme capteur avec la résonance plasmonique localisé comme méthode de transduction (papier n°3). Afin de résoudre certains problèmes associés aux polymères à empreintes moléculaires, tels que l’inhomogénéité en terme de morphologie et de distribution en site de reconnaissance, il a été suggéré d’utiliser des méthodes de polymérisations radicalaire contrôlées. Ces méthodes facilitent aussi leurs synthèses sous forme de nanomatériaux, nanocomposites et films minces. Le quatrième papier considère les récents avantages et inconvénients de ces nouvelles méthodes de polymérisation rapportés aux polymères à empreintes moléculaires. Le dernier papier décrit la première utilisation d’un récente méthode basée sur la polymérisation par transfert à l’iode (ITP), « reversible chain transfer catalyzed polymerization » (RTCP) adapté aux polymères à empreintes moléculaires. Nous décrivons un exemple de synthèse de MIP spécifiques pour la molécule propanolol par RTCP, produisant des polymères sous forme de « bulk » ou particules ayant la même capacité de reconnaissance que ceux synthétisés par polymérisation radicalaire (FRP). La RMN à l’état solide a révélée que la conversion en double liaison intramoléculaire était plus élevée dans le cas de polymères synthétisés par RTCP que par FRP, en particulier à haute concentration en amorceur<br>This thesis is organized in three chapters and is based on three published papers, and two manuscripts about to be submitted. Molecularly imprinted polymers (MIPs) are tailor-made synthetic receptors that are obtained by polymerization in the presence of a molecular template. The first paper describes the use of Raman spectroscopy to detect and quantify the presence of the imprinting template in single molecularly imprinted polymer microspheres. The polymers were imprinted with the Beta-blocking drugs propranolol and atenolol, and precipitation polymerization was used to obtain spherical particles. The nanoparticles were used for bulk detection whereas with micrometer-sized particles, quantitative measurements on single particles were possible. Relatively low detection limits down to 1µM have been reached for the detection of S-propranolol through bulk measurements on MIP nanoparticles. The second paper describes chemical nanosensors with a submicron core-shell composite design, based on a polymer core, a molecularly imprinted polymer (MIP) shell for selective analyte recognition, and an interlayer of gold nanoparticles for signal amplification. SERS measurements on single nanosensors yielded a detection limit of 10-7 M for the Beta-blocker propranolol, several orders of magnitude lower than on plain MIP spheres. These particles were also used as sensor materials with localized surface plasmon resonance measurements as the transduction method (Paper III), for the determination of the Beta-blocking drug propranolol. The sensors were used in suspension and were measured using a standard UV-Vis spectrophotometer. In order to solve general problems associated with MIPs, in particular their heterogeneity in terms of inner morphology and distribution of binding site affinities, it has been suggested to use modern methods of controlled/living radical polymerization for their synthesis. This also facilitates their generation in the form of nanomaterials, nanocomposites, and thin films, a strong recent trend in the field. The fourth paper reviews recent advances in the molecular imprinting area, with special emphasis on the use of controlled polymerization methods, their benefits, and current limitations. In the last paper, we have for the first time used a recently developed CRP method based on iodide mediated polymerization, reversible chain transfer catalyzed polymerization (RTCP), for the synthesis of MIPs. We show on the example of MIPs specific for the Beta-blocking drug propranolol that RTCP is compatible with MIP synthesis, both for the synthesis of bulk polymers and nanospheres, and that it yields polymers with the same binding capacity as the standard FRP method used for comparison. Solid-state NMR measurements revealed that the conversion of pendant vinyl groups was higher with RTCP than with polymers synthesized by FRP, in particular at higher initiator concentrations
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Hsu, Shu-Yao. "Fabrication of Well-Defined Architectures of Ultrahigh-Molecular-Weight Polymers by Living Radical Polymerization." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215574.
Testo completo
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Russum, James. "Controlled Radical Polymerizations in Miniemulsions: Advances in the Use of RAFT." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-10112005-105314/.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--Chemical and Biomolecular Engineering, Georgia Institute of Technology, 2006.<br>Jones, Christopher, Committee Chair ; Schork, F. Joseph, Committee Co-Chair ; Weck, Marcus, Committee Member ; Meredith, Carson, Committee Member ; Agrawal, Pradeep, Committee Member.
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Chaffey-Millar, Hugh William Chemical Sciences & Engineering Faculty of Engineering UNSW. "An experimental and computational study of two state of the art living free radical polymerisation techniques." Awarded by:University of New South Wales. Chemical Sciences & Engineering, 2008. http://handle.unsw.edu.au/1959.4/41421.
Testo completoAbstract (sommario):
This thesis describes the research conducted by t he author in completion of a Doctor of Philosophy in the Centre for Advanced Macromolecular Design(CAMD), Univcrsity of New South Wales (UNSW) , Sydney, Australia; under the supervision of Professor Christopher Barner-Kowollik and Doctor Michelle L. Coote (Australian National University). The research has led to the creation of new knowledge in the fields of free radical polymerisation and chemical kinetics. Research was conducted in two main thrusts: (1) investigation into the governing kinetic processes behind star polymer synthesis via what has become known as a reversible addition fragmentation chain transfer (RAFT), R-group approach and (2) an entirely new mode of living free radical (LFR) polymerisation which has been named thioketone mediated polymerisation (TKMP). In the first broad area of the described research, a novel kinetic modelling scheme has been developed in which only the reactions of a single arm star are simulated explicitly. Subsequently, the molecular weight distributions (MWDs) arising from the single arm star simulation are convolved, using probabilistic calculations, to generate the MWD appropriate to a multi-arm star polymerisat ion bearing t he same kinetic parameters as the single arm one. This model is validated against experimental data, enabling, for the first time, the use of rigorous theoretical reasoning to distill a set of synthetic guidelines for star polymer synthesis via a RAFT, R-group approach. Subsequently, the product spectra resulting from RAFT, R-group approach polymerisations of para-acetoxystyrene have been analysed via mass spectrometry. This has led to direct evidence for many of the complex species whose existence had, up until this point, been inferred from gel permeation chromatography (GPC) measured MWDs. The menagerie of species identified includes, but is not limited to, star-star couples, initiator fragment terminated stars, initiator fragment terminated star-star couples and linear chains -- both living and terminated. Using a kinetic model devised specifically for application in mass spectrometry analysis, the experimentally observed abundances of each of the above species have been compared to t hose predicted by simulation. The qualitative agreement between the predicted and observed abundances has provided additional evidence that t he proposed mechanism for RAFT, R-group approach polymerisations is correct and operative. Further, it seems unlikely that significant, undiscovered kinetic phenomena exist. Due to (a) long simulation times encountered using the state of the art, commercial partial differential equation solver for polymerisation kinetics (i.e. PREDICI, Computing in Technology (CiT), GmbH; see http://www.cit-wulkow.de) and (b) the limited flexibility this software provides with respect to the types of chemical species that can be simulated, fundamental research has been conducted into the kinetic Monte Carlo method to (i) examine fundamental aspects of this simulation approach; (ii) determine the maximum speed attainable through a combination of optimisations including run-time generation of problem specific code and parallelisation; and, therefore (iii) find out what the potential of this method may be as a replacement for t he existing methods. In terms of speed, the developed code outperforms previous Monte Carlo benchmarks in the literature by a factor of 2.6 and the latest developments in the commercial tool, PREDICI that took place during the author's Ph.D. candidature give it similar performance to the herein described Monte Carlo code; however, the latter is required to run on multiple processors in order to compete with the serial algorithm implemented in PREDICI. The Monte Carlo method does, however, provide complete freedom with respect to the chemical species whose kinetics can be simulated, allowing for complex species with many chain lengths and, in principal copolymer compositions and branched structures. The Monte Carlo approach is the method of choice for these types of simulations and for the first time competes with the commercial tool in terms of speed. In the second broad area of the described research, an experimental investigation has been conducted into the applicability of thioketones, S=C (R1) (R2), as mediating agents for free radical polymerisations. The compound di-tert-butyl thioketone (DTBT), S=C-(C(CH3)3)2, has been chosen as a model reagent and this, when incorporated into a free radical polymerisation of styrene has led to a linear increase of the average molecular weight as conversion of monomer into polymer takes place - demonstrating control. A reversible radical trapping mechanism has been proposed and evidence for this has been provided in the form of an ab initio calculation of the equilibrium constant for the trapping of a styryl dimer radical by DTBT. This equilibrium constant was approximately K = 105 L mol-1 and is close to the value which is expected on the basis of the experimental results. To aid future experimental investigations intoTKMP, a quantum chemical survey has, been conducted with the aim of discovering the radical affinities of a large range of thioketones. It has been demonstrated that there is ample scope within this class of compound for potent radical trapping - far above that of DTBT. The affinities of various thioketone substrates for radicals have been understood in terms of the radical stabilising and thioketone destabilising effect of the two substituents R1 and R2 on, respectively, the adduct radical, R-S-C???(R1) (R2), and the parent thioketone. All results appearing in this thesis have been published previously in peer-reviewed scientific journals.
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Vargun, Elif. "Living Radical Polymerization Of Hydroxyethyl Methacrylate And Its Block Copolymerization With Poly(dimethyl Siloxane) Macroazoinitiator." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610605/index.pdf.
Testo completoAbstract (sommario):
Hydrophilic poly(2-hydroxyethyl methacrylate), PHEMA, and hydrophobic poly(dimethyl siloxane), PDMS, segments containing copolymers have been widely used as a biomaterial. These amphiphilic copolymers also used as an emulsifying agent in polymer solutions and compatibilizer in polymer blends. In this case, solution polymerizations of HEMA by radiation, ATRP and RAFT methods were studied. The thermal degradation mechanism of PHEMA, which was prepared in aqueous solution by gamma radiation technique, was studied in detail. The DSC, TGA and Mass Spectroscopy analyses revealed that the degradation is linkage and depolymerization with a combination of monomer fragmentation. The ATRP of HEMA was performed with ethyl-2-bromoisobutyrate (EBriB) initiator and CuCl/bipyridine catalyst in MEK/1-propanol solvent mixture. Cu(II) complexes and PHEMA obtained via ATRP were characterized by UV-vis, FTIR and 1H-NMR analysis. The RAFT polymerization of HEMA with different [RAFT]/[AIBN] ratios were also investigated in three solvents (methyl ethylketone, ethyl acetate and toluene). The controlled polymerization of HEMA with the ratio of [RAFT]/ [AIBN]=18 at 80 oC in MEK and ethyl acetate, shows the first-order kinetic up to the nearly 40 % conversion Macroazoinitiator PDMS-MAI was synthesized from bifunctional PDMS and then copolymerized with MMA, EMA, HEMA and TMS-HEMA monomers Different characterization methods such as FTIR, 1H-NMR, solid state NMR, GPC, XPS, SEM, DSC, etc. have been used for the characterization of block copolymers. P(DMS-b-TMSHEMA) was converted to the P(DMS-b-HEMA) block copolymer by deprotection of TMS groups. The phase separated morphology was observed for the P(DMS-b-HEMA) copolymer, which was different from P(DMS-b-MMA) and P(DMS-b-EMA) copolymers.
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Saoud, Fozi. "Superparamagnetic nanoparticles for synthesis and purification of polymers prepared via controlled/"living" radical polymerization (CLRP)." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/3998.
Testo completoAbstract (sommario):
Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010.<br>ENGLISH ABSTRACT:
Living chains prepared by RAFT polymerization and NMP reactions using Z-carboxylate and Z-phosphate RAFT agents, and X-phosphate NMP initiators, were efficiently attached to the surface of magnetic nanoparticles (MNPs) and used for the separation of dead chains formed in these polymerization reactions prior to the attachment of the RAFT agents and NMP initiators to the surface of MNPs. All the living chains that attach selectively to the surface of MNPs contained RAFT or NMP functionalities, had a low polydispersity index (PDI), and could be reactivated to form new polymer extensions or block copolymers with no detectable deviation from 100% efficiency. RAFT chains prepared by RAFT polymerization using the Z-carboxylate RAFT agent and an excess of free radical initiator were also attached to the surface of MNPs and separated in the presence of an external magnetic field. Separated RAFT-functional chains contained no dead chains formed by combination or disproportionation reactions, but a substantial amount of cross-terminated by-product with a low UV absorbance at 320 nm.
The cross-termination of the intermediate radical formed in the RAFT polymerization reactions was also investigated in the monomer-excluded free radical reaction model of polystyryl benzyl-(4-carboxyl dithiobenzoate) and polystyryl ethyl-2-bromoisobutyrate. The Z-carboxylate 3- and 4-arm star polymers (formed by cross-termination reactions) were then efficiently attached to the surface of MNPs and separated from the remainder of the polymer solution. They were separated from MNPs and characterized by 1H and 13C-NMR spectroscopy, and MALDI-ToF-MS.
Living chains prepared by a RAFT miniemulsion polymerization reaction using Z-carboxylate RAFT agent were attached to the surface of MNPs and used for the separation of all dead chains and uncontrolled high molecular weight polymer of secondary particle formations occur during a miniemulsion polymerization reaction prior to the attachment. Separated dead chains had high PDI values and contained a significant fraction of uncontrolled high molecular weight polymer that lacked RAFT functionality.
Initiator-derived chains formed in RAFT polymerization reactions of styrene (St) and methyl methacrylate (MMA) using phosphate free radical (PFR) initiator were selectively attached to the surface of MNPs and separated from R-group-derived polymer chains in the presence of an external magnetic field. All separated initiator-derived chains contained large fractions of dead chains with weak UV absorbance, and which lacked RAFT functionality, and small fractions of RAFT polymer chains. The separated initiator-derived chains had higher PDI values than the as-prepared polymer in the polymerization of St, but lower PDI values than the as-prepared polymer in the polymerization of MMA.
RAFT agents attached to the surface of MNPs by the Z group were used as mediating agents for the synthesis of polymers grafted to the surface of MNPs. The polymers grafted to the surface of MNPs were separated from the solution of the free polymer by applying an external magnetic field. The amounts of the polymers grafted to the surface of MNPs greatly increased as the number of RAFT agents attached to the surface of MNPs decreased. When ethyl acetate was used as solvent, it reached 65% by weight and 50% by number of chains. Separated polymers grafted to the surface of MNPs had high PDI values and contained RAFT functionality.
Investigations into the kinetics of the RAFT-mediated polymerization reaction on the surface of MNPs revealed that the polymerization reaction mediated using a RAFT agent attached by its Z group to the surface of MNPs had a faster polymerization rate than that mediated using a free Z group RAFT agent. The molecular weight of the grafted polymer increased linearly with conversion, and the reaction rate was pseudo-first-order.<br>AFRIKAANSE OPSOMMING:
Lewende polimeerkettings, berei deur middel van RAFT-beheerde polimerisasie en NMP reaksies waarin Z-karboksilaat en Z-fosfaat RAFT-verbindings en 'n X-fosfaat NMP afsetter gebruik is, is geheg aan die oppervlaktes van magnetisenanopartikels (MNPs), en gebruik vir die skeiding van dooie kettings wat tydens die RAFT en NMP reaksies gevorm is. Alle lewende kettings wat aan die oppervlakte van die MNPs geheg is, is geskei van die oorblywende polimeeroplossing deur die aanwending van ‗n eksterne magnetise veld. Alle kettings wat selektief aan die oppervlaktes van die MNPs gekoppel is met RAFT of NMP funksionaliteit, het ‗n laë poliverspreidingswaarde (PDI) gehad en kon heraktiveer word om ‗n nuwe polimeerverlengings of blokkopolimere te vorm met geen merkbare afwyking van 100% doeltreffendheid nie. RAFT-kettings wat gedurende RAFT-polimerisasie met 'n Z-karboksilaat RAFT-agent en oormaat vrye-radikaalafsetter berei is, is ook geheg aan die oppervlaktes van MNPs en geskei in die teenwoordigheid van 'n eksterne magnetiese veld. Die geskeide RAFT-funksionele kettings het geen dooie kettings bevat nie (gevorm deur kombinasie reaksies), maar 'n aansienlike hoeveelheid ongekontroleerde hoë molekulêremassa polimeer (met lae UV absorpsie by 320 nm).
Die kruis-beëindiging van die intermediêre radikaal wat gevorm is tydens die RAFT-proses is ondersoek in die monomeer-uitsluitende vrye-radikaalreaksiemodel van polistirielbensiel-4-karboksielditiobensoaat en polistirieletiel-2-bromoisobutiraat. Die Z-karboksilaat 3- en 4-arm sterpolimere (gevorm a.g.v. kruis-terminasiereaksies) is effektief geheg aan die oppervlaktes van MNPs en geskei van die res van die polimeeroplossing, en daarna gekarakteriseer met behulp van 1H en 13C KMR, en MALDI-ToF-MS.
Lewende kettings, berei m.b.v. RAFT miniemulsiepolimerisasies met 'n Z-karboksilaat RAFT-agent, is geheg aan die oppervlaktes van MNPs en gebruik vir die skeiding van alle dooie kettings en sekondêre partikels wat tydens die reaksie voor die aanhegting gevorm het. Die geskeide dooie kettings wat agtergebly het, het 'n wye PDI getoon en het 'n aansienlike hoeveelheid ongekontroleerde hoë molekulêremassa polimeer, met geen RAFT-funksionaliteit nie, bevat.
Afsetterafkomstigekettings wat gevorm is tydens die RAFT polimerisasiereaksies van stireen (St) en metielmetakrilaat (MMA) met 'n fosfaat-vrye vrye-radikaalafsetter is selektief geheg aan die oppervlaktes van MNPs en geskei van R-groep-afkomstige polimeerkettings in die teenwoordigheid van 'n eksterne magnetise veld. Alle geskeide afsetter-afkomstige kettings het 'n groot hoeveelheid dooie kettings gehad (met swak UV absorpsie) en met geen RAFT-funksionalilteit nie, en klein fraksies van RAFT-polimeerkettings. Die geskeide afsetter-afkomstige kettings het hoër PDI waardes gehad as die ('as-prepared') polimeer in die polimerisasie van St, maar laer PDI waardes as die ('as-prepared') polimeer in die polimerisasie van MMA.
RAFT-verbindings wat aan die oppervlaktes van die MNPs geheg is deur middel van die Z-groep is as bemiddellingsagente (Eng: mediating agents) gebruik vir die sintese van polimere wat geënt is aan die oppervlakte aan MNPs. Die polimere wat aan die oppervlakte van die MNPs geënt is is geskei van die res van die polimeeroplossing deur die aanwending van ‗n eksterne magnetise veld. Die hoeveelhede van die polimere wat aan die oppervlaktes van die MNPs geënt is het sterk toegeneem namate die aantal RAFT-agente wat aan die oppervlaktes van MNPs geheg is afgeneem het. Wanneer etielasetaat as oplosmiddel gebruik is, was die waardes 55% m.b.t. gewig en 45% m.b.t. die aantal kettings. Die geskeide polimere wat aan die oppervlaktes van MNPs geënt is het hoë PDI getoon en het RAFT-funksionaliteit bevat.
Die kinetika van die RAFT-beheerde polimerisasiereaksies van St, wat gebruik maak van ‗n RAFT-agent wat aan die oppervlakte van die MNPs geheg is deur middel van die Z-groep, is ook ondersoek. Die tempo van polimerisasie was vinniger in die geval waarin die RAFT-agent geheg is deur sy Z-groep aan die oppervlakte van die MNPs as die reaksie met 'n RAFT agent met 'n vrye Z-groep. Die molekulêremassas van die entpolimere het liniêr toegeneem met omsetting, en die reaksie was pseudo-eerste-orde.
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Baek, Kyung-youl. "Synthesis, Characterization, and Functions of Multi-Armed Star Polymers by Metal-Catalyzed Living Radical Polymerization." 京都大学 (Kyoto University), 2002. http://hdl.handle.net/2433/149816.
Testo completo
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Huang, Yun. "Synthesis of Novel Polymer-brush-afforded Hybrid Particles for Well-organized Assemblies." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/189679.
Testo completo
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Kayahara, Eiichi. "Studies on the Precision Control of Polymer Structure Based on Heteroatom-Mediated Living Radical Polymerization Reaction." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142245.
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Nishimori, Kana. "Molecular Design for Precise Sequence Control and Functions of Alternating Copolymers." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/253306.
Testo completoAbstract (sommario):
京都大学<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第22470号<br>工博第4731号<br>新制||工||1739(附属図書館)<br>京都大学大学院工学研究科高分子化学専攻<br>(主査)教授 大内 誠, 教授 秋吉 一成, 教授 竹中 幹人<br>学位規則第4条第1項該当<br>Doctor of Philosophy (Engineering)<br>Kyoto University<br>DGAM
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Nilsen, Aaron. "The design, synthesis and testing of n-alkoxy amine initiators for nitroxide-mediated 'living' free radical polymerization /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2005. http://uclibs.org/PID/11984.
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Kimura, Yoshihiko. "Self-Assembled Polymer Materials : From Amphiphile Design to Nanostructure Control." Kyoto University, 2020. http://hdl.handle.net/2433/259742.
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Franco, Ivan Carlos 1976. "Modelagem matematica da polimerização via radical livre controlada usando mecanismo RAFT (transferencia de cadeia reversivel por adição-fragmentação)." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266173.
Testo completoAbstract (sommario):
Orientador: Liliane Maria Ferrareso Lona<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica<br>Made available in DSpace on 2018-08-07T23:37:08Z (GMT). No. of bitstreams: 1
Franco_IvanCarlos_M.pdf: 1044560 bytes, checksum: 8f4fdd66626d63245a2131f55b09f807 (MD5)
Previous issue date: 2007<br>Resumo: Polimerização via radical livre controlada (CRP) tem recebido cada vez mais atenção como uma técnica para produção de polímeros com micro estrutura altamente controlada. Em particular, distribuições de pesos moleculares estreitas são obtidas, com polidispersidade muito próxima de um, sendo um campo promissor na ciência de polimerização com estruturas controladas. Um importante requisito para engenharia de polimerização e desenvolvimento de polímeros é a construção de modelos matemáticos úteis, especialmente aqueles de natureza mecanística, com validação experimental. O objetivo deste trabalho é o desenvolvimento de modelos matemáticos abrangentes para simulação de polimerização para mecanismo RAFT. Metacrilato de metila em benzeno a 60°C na presença de 2,2-cianopropil 1- pirrolecarboditioato (agente RAFT) e com AIBN como iniciador em um reator batelada será considerado como estudo. Os pesos moleculares foram calculados
utilizando o método dos momentos. Uma análise paramétrica considerando o efeito da concentração de iniciador e da concentração de agente RAFT foi realizada. O modelo predito está de acordo com os dados experimentais da literatura, o que atesta sua validade para ser utilizado
no controle de estruturas poliméricas obtidas no processo RAFT<br>Abstract: Lately, Living Free Radical Polymerization (LFRP) has been detached as a technique for the production of polymers with highly controlled microstructure. In particular, narrow distributions of molecular weights are obtained, with polydispersity values next to one. So, this technique is a promising field in the science of polymerization with controlled structures. An important requirement for engineering of polymerization and polymer development is the construction of useful mathematical models, especially those of mechanistic nature, with
experimental validation. The objective of this work was to develop comprehensive mathematical models to simulate polymerization from RAFT mechanism. Methyl Methacrylate in benzene at 60°C in the presence of 2-cyanoprop-2-yl 1-pyrrolecarbodithioate (agent RAFT)
and with AIBN as the initiator in a batch reactor was considered. The molecular weights have been calculated using the method of moments.
A parametric analysis considering the effect of the initiator and agent RAFT concentrations was performed. Models prediction showed good agreements with experimental data from literature, what certifies its validity in being used in the control of polymeric structures in RAFT process<br>Mestrado<br>Desenvolvimento de Processos Químicos<br>Mestre em Engenharia Química
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Kir, Onur [Verfasser], Wolfgang H. [Akademischer Betreuer] Binder, and Guido [Akademischer Betreuer] Kickelbick. "Surface initiated polymerization of isoprene from silica nano- and glass particles via living anionic and controlled radical polymerization techniques / Onur Kir. Betreuer: Wolfgang H. Binder ; Guido Kickelbick." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2013. http://d-nb.info/1050977734/34.
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Ogura, Yusuke. "Tandem Transesterification in Polymer Synthesis： Gradient and Pinpoint‐Functionalized Polymers." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225629.
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Lee, Sang-Ho. "Supramolecular Self-Assembly of Well-Defined Polymers:Positional Programming of Complementary Hydrogen Bonds." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/189675.
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Ansong, Omari E. "Preparation and Evaluation of Novel Initiators for the Thermally Mild Living and Controlled Free Radical Polymerization of Methacrylates: Potential Application in Dental Composite Resins." Diss., Temple University Libraries, 2008. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/17521.
Testo completoAbstract (sommario):
Chemistry<br>Ph.D.<br>A number of nitroxide adducts and N-acyloxytrialkylammonium salts were prepared, isolated, characterized and evaluated as initiators for the controlled and living free radical polymerization of methacrylate and dimethacrylate monomers under mildly thermal and photochemical conditions. The initiators and polymerization methods that were developed could potentially be used for improving resins employed in dental applications.
Using very easy synthesis strategies, the following nitroxide initiators were prepared in high purity, isolated and characterized: 1-Benzoylperoxy-2,2,6,6-tetramethyl-piperidine (BPO/TEMPO), 1-(2'-Cyano-2'-propoxy)-2,2,6,6-tetramethylpiperidine (AIBN/TEMPO), 1,1-ditertbutyl-1-(1-methyl-1-cyanoethoxy)-amine (AIBN/DBN), 1,1-ditertbutyl-1-(benzoylperoxy)-amine (BPO/DBN) and 2,2,6,6,-tetramethyl-4-oxo-1-(1-methyl-1-cyanoethoxy)-piperidine (AIBN/4-OXO-TEMPO). Using H2SO4 additive and an improved unimolecular initiation in nitroxide mediated polymerization, living and controlled polymerization of methyl methacrylate (MMA), tri-ethylene glycol dimethacrylate (TEGDMA) and ethoxylated bisphenol A dimethacrylate (EBPADMA) were accomplished, for the first time ever for most of the initiators. Linear polymers (PMMA) were produced in high yield (93 %) under mildly thermal conditions (T = 70 oC) and with excellent attributes: (PDI = 1.04-1.26), Mn (87000), Tg (122-128 oC), Td (290-410 oC). Highly crosslinked polymers, poly(TEGDMA) and poly(EBPADMA), were produced in high yield (100 %) with Td (350-400 oC). The initiators were stable for a year and half at 0 oC.
Two routes were investigated for the preparation of N-acyloxytrialkylammonium salts. The more efficient of these routes was used to make several novel analogs of the salts. The salts were evaluated for the free radical polymerization of MMA, TEGDMA and EBPADMA under mildly thermal (T = 60 oC) conditions with and without H2SO4 additive. Polymerization rate, yield and polymer attributes all improved upon application of H2SO4 additive. PMMA was produced with excellent attributes (PDI = 1.01-1.06), Mn (96,000-122000), Td (330-385) and Tg (127-134). Highly crosslinked poly(TEGDMA) and poly(EBPADMA) were produced with Td ranges of 300-374 oC and 375-411 oC respectively.<br>Temple University--Theses
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Černý, Miroslav. "Vinylové předpolymery - metody přípravy a využití." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-216844.
Testo completoAbstract (sommario):
The theoretical part of this thesis is focused on bulk radical polymerization of styrene, methylmethacrylate, vinyltoluene and paramethylstyrene. It summarizes actual informations about kinetics and performance possibilities of bulk polymerization. Experimental part deals with polystyrene prepolymers preparation by bulk polymerization. The aim is to find optimal conditions for prepolymers preparation. Prepolymers should be usable for subsequent polymerization nearly up to 100% conversion. Conversion values were gravimetrically determined and molecular weights were obtained by viskosity measurements, which were realized by Ubbelohde viscometer. In the experimental part, there were performed simulations targeted on conversion dependence on time. The purpose was a prediction of monomer conversion at a given time during polymerization. Differences between reality and simulation were low in most of cases and the found form of kinetic behavior calculations provides satisfying results. In the conclusion of this thesis was suggested a new procedure for polystyrene prepolymers preparation.
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Bui, Nhat Thi Hong. "Polyhydroxyl and Polyphosphorylcholine functionalized Silica for Hydrophilic interaction liquid Chromatography- Synthesis, characterization and application." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-60600.
Testo completoAbstract (sommario):
This thesis focuses on the development of new stationary phases for use in hydrophilic interaction liquid chromatography using TRIS-based and phosphorylcholine typed monomers and porous silica particles as starting substrates. In this thesis, several ways of polymerizing highly hydrophilic monomers onto pore surfaces of silica supports are described, based on several “grafting from” schemes. “Controlled/living” radical polymerizations including atom transfer radical polymerization (ATRP) and iniferter-mediated polymerization in conjunction with conventional free radical polymerization are demonstrated to be successful tools for grafting different hydrophilic monomers (polyhydroxyl and phosphorylcholine [meth]acrylamide/acrylates) onto the silica surfaces. Reaction solvents are proven to play an essential role to achieve efficient graft polymerization of activated silica surfaces with these amphiphilic vinylic monomers, which is difficult because of their restricted access to the activated surface in solvents that can be used because of solubility constraints. Two tentacle TRIS-based polymer grafted silica, namely TRIS-WAX – TRIS functionality bonded to silica via a C–N–C imine bond and TRIS-Amide – TRIS bonded to silica via an amide bond, prove to be useful as stationary phases for hydrophilic interaction chromatography (HILIC).The TRIS-WAX exhibits a mixed mode hydrophilic partitioning and weak anion exchange (HILIC/WAX) retention mechanism while retention by hydrophilic partitioning is the dominant mechanism on the neutral TRIS-Amide phase which lacks weak anion exchange (WAX) properties. Interestingly, both these phases have selectivities that are radically different from most commercial HILIC stationary phases. Finally, a method is demonstrated for synthesizing a stratified (graft-copolymerized) silica material based on N,N′-methylenebisacrylamide and 2-methacryloyloxyethyl phosphorylcholine (MPC) using a “controlled/living” photoiniferter-mediated polymerization from the N,N-diethyldithiocarbamate iniferter moiety immobilized silica surfaces. This polymerization method proves to be successful for graft-blockcopolymerization of different highly hydrophilic monomers onto the activated surfaces of porous silica. In this way, silica surfaces are grafted with a cross-linked amide-based hydrogel, on top of which a tentacle zwitterionic phosphorylcholine-typed layer is synthesized. The resulted material proves to be useful for HILIC separations and possesses different selectivity for the tested organic acids compared to that of commercial ZIC-cHILIC stationary phase.
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Kwak, Yungwan. "Kinetic studies on living radical polymerizations." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144032.
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Lahoud, Isabelle. "Contribution à la détermination de cinétiques de polymérisation radicalaire conventionnelle et RAFT en solution par calorimétrie." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR029.
Testo completoAbstract (sommario):
L’essentiel de ce travail de thèse a porté sur l’étude calorimétrique de la polymérisation radicalaire en solution. Les paramètres cinétiques de deux systèmes de polymérisation ont été déterminés : ceux de la polymérisation conventionnelle et ceux de la polymérisation contrôlée par transfert de chaine réversible par addition-fragmentation (RAFT). La méthode d’estimation des paramètres cinétiques est basée sur la comparaison du profil de puissance thermique expérimental libéré lors de la polymérisation et mesuré à l’aide d’un calorimètre réactionnel avec le profil de puissance calculé au moyen du modèle proposé. Les paramètres cinétiques ont été estimés à l’aide d’une méthode de minimisation basée sur un algorithme génétique. La synthèse choisie dans cette étude est la polymérisation radicalaire du méthacrylate de butyle dans différents solvants organiques. Un modèle global et des modèles plus détaillés prenant en compte les principales étapes de la polymérisation ont permis de reconstruire le profil de puissance dégagé par la réaction en fonction de la température de synthèse. Par ailleurs, les propriétés physico-chimiques du produit obtenu ont été analysées pour étudier la relation entre les paramètres cinétiques et les propriétés des polymères. Les effets de quatre solvants organiques (anisole, cyclohexanol, cyclohexanone, xylène) ainsi que des conditions opératoires (notamment la concentration en monomère et la température) ont été mis en évidence. D’autres techniques d’analyse thermique ont été utilisées, permettant de valider les paramètres estimés<br>This work focused on the calorimetric study of solution radical polymerization. The kinetic parameters of two polymerization systems have been investigated: those of conventional radical polymerization and that controlled by Reversible Addition-Fragmentation chain Transfer polymerization (RAFT). The method for estimating the kinetic parameters is based on the comparison of the experimental thermal power profile released during the polymerization and measured using a reaction calorimeter with power profiles calculated using the proposed model. Kinetic parameters were estimated using a minimization method based on a genetic algorithm.The synthesis chosen in this study is the radical polymerization of butyl methacrylate in various organic solvents. A global model and more detailed models taking into account the main polymerization steps made it possible to reconstruct the power profile released by the reaction at various synthesis temperatures.Furthermore, the physicochemical properties of the final product were analyzed in order to study the relationship between the kinetic parameters and the produced polymer properties. The influence of four organic solvents (anisole, cyclohexanol, cyclohexanone, xylene) as well as the operating conditions (in particular the monomer concentration and the temperature) was discussed. Other thermal analysis techniques were used to validate the estimated parameters
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Moreno, Guerra Adrian. "Cu(0) wire-mediated SET-LRP in biphasic systems and development of stimuli cleavable polymers." Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/670490.
Testo completoAbstract (sommario):
La polimerització radicalària controlada catalitzada per Cu(0) es una de les metodologies més importants en l’àmbit de les polimeritzacions radicalàries degut a seva simplicitat i la possibilitat de sintetitzar polímers amb estructures ben definides i arquitectures complexes. En aquesta mateixa línia el desenvolupament de sistemes polimèrics capaços d’encapsular i alliberar fàrmacs es una de les línies de investigació més explotades e investigades en els darrers anys, ja que millorar la solubilitat de fàrmacs hidrofòbics i alliberar-los sota la presencia de certs estímuls biològics segueix sent una tasca bastant laboriosa.
El objectiu principal d’aquesta tesis es investigar la polimerització radicalària catalitzada per Cu(0) en presencia de sistemes bifàsics i tanmateix explorar el potencial i les limitacions d’aquesta metodologia per obtindré polímers amb una estructura perfectament definida. En ultima instancia l’aplicació d’aquest tipus de polimerització radicalària catalitzada i altres mètodes de polimerització seran emprats per la síntesi de polímers sensibles a certs estímuls i amb la finalitat d’encapsular fàrmacs per actuar com vehicles en l’alliberació controlada dels mateixos.<br>La polimerización radicalaria catalizada por Cu(0) es una de las principales metodologías en el campo de las polimerizaciones radicalarias debido a su alto grado de simplicidad i la posibilidad de sintetizar polímeros con estructuras perfectamente definidas. En esta misma línea el desarrollo de sistemas poliméricos capaces de encapsular fármacos es una línea de investigación en constante desarrollo y de gran interés ya que la necesidad de mejorar la solubilidad de fármacos hidrofóbicos y liberarlos bajo la presencia de determinados estímulos de biológica relevancia sigue siendo una tarea complicada.
El objetivo principal de esta tesis es investigar la polimerización radicalaria catalizada por Cu(0) en sistemas bifásicos con el objetivo de obtener polímeros con un alto grado de estructura definida. En última instancia la aplicación de este tipo de polimerización radicalaria junto con otros métodos de polimerización será empleado para el desarrollo de polímeros sensibles a ciertos estímulos de biológica relevancia con la finalidad encapsular fármacos y liberarlos de manera controlada.<br>Cu(0)wire-catalyzed SET-LRP has been postulated as one of the most versatile LRP techniques due to its operational simplicity which enables the construction of well-defined polymers and more complex architectures. In particular, the development of polymeric materials with suitable applications for medicine (e.g. polymeric nanoparticles able to encapsulate and release drugs) is a field of growing interest since they improve the poor solubility of hydrophobic drugs in aqueous media. However, their selective delivery under the application of different biological relevant stimuli still remains challenging.
The main objective of this thesis is to investigate the Cu(0)wire-catalyzed SET-LRP in “programmed” biphasic systems and to explore the potential and limitations of this methodology with the ultimate goal of obtaining well-defined polymers with complex architectures and maximum end-group fidelity. Eventually, the application of biphasic SET-LRP and other polymerization techniques has been used for the synthesis of stimuli cleavage polymers and their potential application as drug delivery systems has been studied.
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Zhang, Wenjing. "Auto-assemblage de copolymères à blocs amphiphiles induit par la polymérisation : vers des édifices polymères à architecture, morphologie et propriétés contrôlées." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10222/document.
Testo completoAbstract (sommario):
L’objectif principal de ce travail de thèse est de synthétiser par polymérisation RAFT en milieux homogène et hétérogène des copolymères à blocs amphiphiles de structure bien contrôlée. Un procédé simplifié, « ont pot » a donc été développé pour synthétiser ces copolymères et les auto-assembler en particules dans l’eau. Cette méthode dite de « l’auto-assemblage induit par la polymérisation » (PISA) permet de synthétiser en quantité des copolymères à blocs amphiphiles en milieux aqueux sans aucune étape de purification intermédiaire. Dans ce procédé, deux étapes successives sont effectuées dans le même réacteur. La 1ère étape a pour but de synthétiser des agents RAFT macromoléculaires hydrophiles (macroRAFTs) par polymérisation en solution dans l’eau. Ces macroRAFTs fonctionnalisés par un groupement trithiocarbonate sont ensuite utilisés dans le même réacteur comme agents de contrôle etprécurseurs de stabilisants pour la polymérisation en émulsion du monomère hydrophobe directement dans l’eau. Lors de cette 2nde étape, des copolymères à blocs amphiphiles sont formés et s’auto-assemblent sous forme de particules aux morphologies variées (sphères, filaments et vésicules). Nous avons alors étudiés les différents paramètres (pH, température de polymérisation en émulsion, nature des monomères hydrophobe et hydrophile, taux de solide, masses molaires des blocs hydrophobe et hydrophile, etc)gouvernant la formation de morphologies spécifiques. Un objectif supplémentaire a été l’étude du comportement viscoélastique linéaire des suspensions de ces nano-fibres polymère à une température inférieure (25°C) ou supérieure (130°C) à la température de transition vitreuse (Tg) du coeur polystyrène des nano-fibres. A T < Tg, les nano-fibres sont parfaitement rigides et obéissent à une dynamique brownienne de bâtonnets. En effet, les lois d’échelles déduites du comportement viscoélastique de ces suspensions obéissent aux lois prédites par Doi-Edwards. En revanche, ces nano-fibres sont flexibles pour T > Tg et ont une dynamique Brownienne de chaînes polymères en solution<br>The aim of this work was synthesis of well-defined amphiphilic block copolymers in homogenous and heterogenous media using RAFT polymerization (Reversible Addition-Fragmentation Chain Transfer) and to study their self-assemblies in water. A one-pot process in water was developed for the synthesis of amphiphilic block copolymers that simultaneously to their growth self-assembled into nano-particles. This method called “polymerization-induced self-assembly” (PISA) allows the synthesis of large quantities of amphiphilic block copolymers in aqueous media without any intermediate purification step. During this process, two successive polymerization steps are performed in the same reactor. The first step consists in the synthesis of the hydrophilic macromolecular RAFT agents (macroRAFT agents) possessing a trithiocarbonate reactive group via RAFT in water. Without purification, these macroRAFT agents are reactivated for the polymerization of a hydrophobic monomer in the same reactor via RAFT emulsion polymerization. The resulting amphiphilic block copolymers self-assembled into nano-objects with various morphologies (spherical micelles, nanofibers and vesicles). Different parameters (pH, temperature, natureof hydrophilic and hydrophobic monomers, solids contents, molar masse of hydrophilic and hydrophobic blocks, etc) control these morphologies. Besides, the viscoelastic properties of polymeric nanofibers suspensions were studied as a function of the temperature. Below the Tg of polystyrene core at 25°C, the scaling law from viscoelastic behavior of these nanofiber suspensions the Doi−Edwards theory on the Brownian dynamics of rigid rods. Above Tg at 130°C, the nanofibers are flexible and it observed that their dynamics obey the power laws for polymer chains in solution
44
Goto, Atsushi. "Kinetic Studies on Living Radical Polymerizations with Particular Reference to Activation Processes." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/77889.
Testo completo
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Griveau, Lucie. "Emulsion polymerization in the presence of reactive PEG-based hydrophilic chains for the design of latex particles promoting interactions with cellulose derivatives." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1329/document.
Testo completoAbstract (sommario):
Dans cette thèse, des particules de polymère fonctionnalisées en surface avec des groupes poly (éthylène glycol) (PEG) ont été synthétisées pour favoriser leur interaction avec les dérivés cellulosique via liaisons hydrogène intermoléculaires. Deux voies de synthèse ont été proposées pour obtenir ses composites cellulose/latex.La première voie est basée sur l'auto-assemblage induit par polymérisation (PISA) pour former des nanoparticules fonctionnalisées avant leur adsorption sur un substrat cellulosique. La PISA tire profit de la formation de copolymères blocs amphiphiles dans l'eau en combinant la polymérisation en émulsion avec les techniques de polymérisation radicalaire contrôlées (RDRP). Ces dernières sont utilisées pour synthétiser des polymères hydrophiles agissant à la fois comme précurseur pour la polymerization en émulsion d'un monomère hydrophobe, et comme stabilisant des particules de latex obtenues. Deux techniques de RDRP ont été étudiées : les polymérisations RAFT et SET-LRP. Des polymères hydrophiles à base de PEG de faible masse molaire ont été synthétisés en utilisant ses deux techniques qui sont ensuite utilisés pour la polymérisation d'un bloc hydrophobe dans l'eau. Le transfert de l'agent de contrôle au site de la polymérisation était difficile en utilisant la SET-LRP en émulsion, conduisant à la formation de larges particules. En utilisant la RAFT en émulsion, des particules nanométriques ont été obtenues, avec un changement morphologique observé en fonction de la taille du segment hydrophobe, puis adsorbées sur des nanofibrilles de cellulose (CNF).La seconde voie utilise la polymérisation en émulsion classique réalisée en présence de nanocristaux de cellulose (CNC) conduisant à une stabilisation Pickering des particules de polymère. L'interaction cellulose/particule est assurée grâce à l'ajout d’un comonomère à type PEG. Une organisation a été visualisé dans laquelle plusieurs particules de polymère recouvrent chaque CNC<br>In this thesis, polymer particles surface-functionalized with poly(ethylene glycol) (PEG) groups were synthesized to promote their interaction with cellulose derivatives via intermolecular hydrogen bond. Two synthetic routes were proposed to obtain such cellulose/latex composites.The first route was based on the polymerization-induced self-assembly (PISA) to form functionalized polymer nanoparticles prior to adsorption onto cellulosic substrate. PISA takes advantage of the formation of amphiphilic block copolymers in water by combining emulsion polymerization with reversible-deactivation radical polymerization (RDRP) techniques. The latter were used to synthesize well-controlled hydrophilic polymer chains, acting as both precursor for the emulsion polymerization of a hydrophobic monomer, and stabilizer of the final latex particles. Two RDRP techniques were investigated: reversible addition-fragmentation chain transfer (RAFT), and single electron transfer-living radical polymerization (SET-LRP). Low molar mass PEG-based hydrophilic polymers have been synthesized using both techniques, used for the polymerization of a hydrophobic block in water. The transfer of controlling agent at the locus of the polymerization was challenging for SET-LRP in emulsion conditions leading to surfactant-free large particles. Nanometric latex particles were obtained via RAFT-mediated emulsion polymerization, with morphology change from sphere to fibers observed depending on the size of the hydrophobic segment, which were then able to be adsorbed onto cellulose nanofibrils (CNFs).The second route used conventional emulsion polymerization performed directly in presence of cellulose nanocrystals (CNCs) leading to Pickering-type stabilization of the polymer particles. Cellulose/particle interaction was provided thanks to the addition of PEG-based comonomer. Original organization emerged where CNCs were covered by several polymer particles
46
Hu, Yu-Hsiang, and 胡毓祥. "Investigation of Novel Living Radical Polymerization." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/49729305675873329354.
Testo completoAbstract (sommario):
博士<br>國立成功大學<br>化學工程學系碩博士班<br>93<br>Abstract
Living radical polymerization of vinyl monomer by thiol and lactam as initiator was investigated in this thesis, including the mechanism, reactivity of copolymerization, and thermal degradation behavior. Proton is transferred from thiol to lactam group and forms the inter-medium structure, thiolamide, as the active specie during the initiation step. Propagation reaction, thereby, occurs via monomer insertion from the terminal group of the polymer chain end. Molecular weight can be controlled by the monomer-to-thiol ratio. Lactam in this system acts as a capping agent, which in terms to control the tactility and the dynamic equilibrium of activation/deactivation process. In addition, polymers prepared by this route have high glassy transition temperatures due to the high proportion of syndiotactic conformation produced. Solvent effects were also examined to reveal the evidence of capping agent on the polymerization rate, tactility, and molecular weight distribution. Since the absence of termination reaction in the system, polymers without vinyl-bond are generated, which causes the high thermal stability. For copolymerization, the polymerization rate enhanced by adding a few mole ratio of comonomer bearing with electron withdraw group, meanwhile the reactivity will also vary accordingly. Finally, well-defined block copolymers were successfully synthesized by this novel approach.
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Jiang, Jian-Sing, and 江建興. "Living free radical polymerization of styrene." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/95718194831044756910.
Testo completoAbstract (sommario):
碩士<br>國立臺灣科技大學<br>化學工程系<br>101<br>Reversible addition-fragmentation chain transfer(RAFT) polymerization was investigated.The RAFT agent used dibenzyltrithiocarbonate (DBTTC).13C-NMR、1H-NMR、DSC were used to verify the structure,purity,and melting point of DBTTC.In RAFT polymerization with DBTTC,toluene was used as solvent,and styrene used as monomer.The molecular weight distribution attained is in the range 1.4-1.8 due to solvent and initiator effects at 60℃,70℃,80℃,and 100℃.Using bulk polymerization,the ratio of RAFT agent to initiator was varied,and molecular weight distribution is in the range 1.4-1.69 at 80℃,and 110℃.In thermal polymerization at 100℃,110℃,and 120℃,the product in the absence of RAFT agnet has a very high molecular weight,and molecular weight distribution is very broad(PDI>2).With different levels of RAFT agent,molecular weight distribution is in the range 1.25-1.35.Chain extension with the same monomer results higher in molecular weight,and a broader distribution(PDI=1.47).Block polymer was prepared by using 2-Ethylhexyl Acrylate(2-EHA) and different initiators.At 80℃,molecular weight is bigger than 110℃.The molecular weight distribution is in the range 1.8-2.3.
48
CHIH-CHIANG, LIN, and 林志強. "Study of Living Free Radical Polymerization Process." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/57586577279394789520.
Testo completoAbstract (sommario):
碩士<br>國立臺北科技大學<br>有機高分子研究所<br>89<br>The waste tire surface modifications were investigated by living free radical polymerizations. The potential applications were discussed in this research.
Polypropylene﹙pp﹚ is a very important polymer for textile and engineering application. In this work, a living free radical graft polymerization was used to modify the surface properties of pp.
A block copolymer of styrene and acrylic acid was synthesized by using the nitroxide free radical polymerization.
The materials have potential application as compatibilzer in polymer blend.
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徐倍崇. "A study on living free radical polymerization." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/38482613671225962010.
Testo completoAbstract (sommario):
碩士<br>國立臺北科技大學<br>有機高分子研究所<br>92<br>PET is grafted with acrylic acid by living free radical polymerization .
The contact angles change from 78∘to 60∘. The chemical reaction is identified by FT-IR . Polyacrylic acid is also grafted with styrene by the same synthetic scheme .
On the other hands . ABS is graft with acrylic acid . They have potential applications in compatibilizers for composites.
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Chien-Chih, Chen, and 陳建志. "A Study on Living Free Radical Polymerization." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/59778765741776930540.
Testo completo