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1
Bechthold, Nina. "Polymerisation in Miniemulsion". Phd thesis, [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961879416.
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Greenhalgh, Edward T. "Fundamental understanding of microwave assisted ring-opening polymerisation and co-polymerisation". Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14265/.
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The work presented in the thesis attempted to gain in-depth understanding of the effect that the microwave energy has on various facets of the ring-opening polymerisation of cyclic esters with a view to synthesising novel bio-degradable homopolymers, branched structures and copolymers. Chapter 1 introduces the various synthetic polymer procedures and lists possible final product architectures. The main technique that is used throughout this thesis, ring-opening polymerisation, is discussed in great detail. The various targeted linear aliphatic polyesters are introduced. Finally, the fundamental theory behind microwave dielectric heating is discussed. Chapter 2 outlines the various characterisation techniques that are used to analyse the various synthesised materials throughout the work in this thesis. The polymerisation techniques used, particularly using the microwave reactor, is also discussed. In Chapter 3, the effect that microwave heating has upon the homopolymerisation of poly(ε-caprolactone) is investigated. Detailed analysis of the dielectric properties of the reagents and accurate temperature monitoring is applied at various stages of the reaction mechanism to compare and contrast the effect of microwave and conventional heating. Chapter 4 describes the impact that microwave energy has upon the copolymerisation reactions when a second cyclic ester is introduced, D/L-lactide. Various procedures are utilised in an attempt to synthesise bio-degradable block copolymers with interesting mechanical properties and degradation rates. The dielectric properties of the reagents and their polymer structures are used to rationalise any experimental observations. The work presented in Chapter 5 investigates the synthesis of branched polymers using a di-lactone branching agent, composed to two joined ε-CL units. Various analytical techniques are employed to guarantee successful branching. The effect of microwave energy is scrutinised, with a view to creating faster rates of reaction and altering the final product structure using direct dielectric heating. Finally, Chapter 6 provides the overall conclusions obtained from the work presented in this thesis, before providing possible routes of subsequent study for further research into this area.
3
Zaher, Damien. "Early transition metal benzimidazolyl-based catalysts for olefin polymerisation and co-polymerisation". Thesis, Imperial College London, 2007. http://hdl.handle.net/10044/1/8352.
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Fonseca, Jose Luis Cardozo. "Plasma polymerisation of organosilanes". Thesis, Durham University, 1994. http://etheses.dur.ac.uk/10490/.
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Shooter, Andrew James. "Living free radical polymerisation". Thesis, University of Warwick, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263817.
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Snell, David John. "Ultrasonically assisted emulsion polymerisation". Thesis, University of Bath, 2002. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760798.
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Smit, Madri. "Polymerisation of 1,5-hexadienes". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52403.
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Thesis (MSc)--Stellenbosch University, 2001.ENGLISH ABSTRACT: In this study, the feasibility of the non-conjugated 1,5-hexadiene as monomer in metallocene catalised cyclopolymerizations was considered. Homopolymers and copolymers with ethylene, propylene, 1-pentene, 1-hexene and 2-methyl-1,5- hexadiene as comonomers were synthesised in the presence of Cp2ZrCh and rac-Et(lnd)2Zrh. The microstructure (stereoregularity and cyclisation) and number-average molecular weight were determined from NMR analysis. Crystalline oligomers with functional (eg -OH) and vinylidene end groups were obtained.
AFRIKAANSE OPSOMMING: Die studie behels die ondersoek rakende die gebruik van ongekonjugeerde 1,5- heksadieen as monomeer in metalloseengekataliseerde polimerisasies. Homopolimere, sowel as kopolimere van etlieen, propileen, 1-penteen, 1- hekseen en 2-metiel-1,5-heksadieen, is in die teenwoordigheid van Cp2ZrChen rac-Et(lnd)2ZrCI2 gepolimeriseer. Die mikrostruktuur (stereochemie en siklisering) en die getal-gemiddelde molekulêre gewig van die gesintetiseerde polimere is met behulp van KMR spektroskopie ondersoek. Die studie het getoon dat kristallyne oligomere met funksionele (bv -OH) en vinilideen endgroepe gesintetiseer is.
8
Alger, Luke. "Dispersion polymerisation of divinylbenzene". Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/34134.
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Particles containing 55% divinylbenzene (DVB) have been prepared using dispersion polymerisation. The steric stabilisers that have been utilised are partially hydrolysed poly(vinyl acetate)s, poly(ethylene oxide) and a poly(ethylene oxide) macromonomer in methanolic media. The concentrations of stabiliser, monomer and initiator have been varied to investigate the influence that they have on the particle size and the particle size distribution. The particles have been characterised by scanning electron microscopy (SEM) for a visual impression of the particles in addition to laser diffraction particle size analysis and hydrodynamic chromatography (HDC) for particle size.
9
Walton, Mark. "New pre-catalysts for olefin polymerisation and ring-opening polymerisation of lactides/lactones". Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/50548/.
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A number of pre-catalysts featuring phenoxyimine, phenolate and calixarene ligand systems have been synthesized, characterised and screened for their ability to polymerize α-olefins or ring open polymerize (ROP) cyclic esters. The treatment of a number of related phenoxyimine ligands (L1H – L3H, L6H – L14H) and bridged phenoxyimines (L4H2 and L5H2) with vanadium trichloride (VCl3), vanadium oxytrichloride (VOCl3) or vanadium oxytripropoxide (VO(OnPr)3) afforded the compounds 1 – 20. Compounds 21, 22 and 23 were isolated from the reaction between VO(OnPr)3 and diphenolate ligand (L15H2) or bridged diphenolates (L16H4 or L17H4) respectively. Treatment of the alkali vanadium compound (LiVO(OtBu)4) with tert-butylcalix[6]arene (L18H6) afforded compound 24, while on a number of syntheses, the minor 1D polymeric compound 25 was also obtained. Whilst the reaction between tert-butylcalix[8]arene (L19H8) and NaVO(OtBu)4 led to the formation of compound 26, the use of the alkali free VO(OtBu)3 resulted in the formation of two solvates of compound 27. Imidazole (L20H), oxazole (L21H), α-diimine (L22), iminopyridine (L23, L24) and phenoxyimine (L25H – L29H) ligand sets have been treated with group 5 (Nb or Ta) chlorides or oxytrichlorides to afford compounds 28 – 50, which have been fully characterised. The screening of group 5 compounds 1 – 50 for the polymerisation of α-olefins revealed high activity, significantly in the case of the niobium precatalysts which were two orders of magnitude above the previously reported compounds. The reactions between 1,3-dipropoxy-p-tert-butyl-calix[4]arene (L30H2), hexahomotrioxacalix[3]arene (L31H3) or tripropoxy-p-tert-butylcalix[4]arene (L32H) with zinc or magnesium alkyls has been explored, resulting in the isolation of compounds 51 – 58, which includes a number of heterobimetallic compounds. While all of the zinc and magnesium compounds screened were found to be active for the ring opening polymerisation of either ε-caprolactone or rac-lactide, compound 58, featuring a tripropoxy-p-tert-butylcalix[4]arene (L32H) ligand with a magnesium n-butyl group was found to exhibit exceptional activity and immortal character.
10
Laryea, Esther [Verfasser]. "Einfluss der Fluiddynamik auf Polymerisationen am Beispiel der freien radikalischen Polymerisation von Methylmethacrylat / Esther Laryea". München : Verlag Dr. Hut, 2020. http://d-nb.info/1219471089/34.
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Ferenz, Michael. "Polymerisation von Methylmethacrylat mit Zirconocenen". [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964911515.
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Bruckmann, Monika. "Polymerisation von Acrylnitril mit Zirkonocenen". [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970850980.
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Stainforth, D. B. "Some studies of radical polymerisation". Thesis, Lancaster University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234666.
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Drewitt, Mark Jeremy. "Metallocenophanes : synthesis, characterisation and polymerisation". Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267957.
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Noël, Caroline. "Plasma polymerisation : study and application". Thesis, Durham University, 2009. http://etheses.dur.ac.uk/2104/.
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Molecular interactions are often studied using immobilised organic and biological entities at the surface of a substrate. Functionalisation of such surfaces can be achieved via different technologies such as Langmuir-Blodgett films, self-assembled monolayers and spin-coated layers. The main drawback of these methods is the dependence on the substrate, limiting the scope of possible applications. Conversely, plasma polymerisation entails the deposition of thin polymeric films at the surface of a wide variety of substrates. The development of pulsed plasma has opened new paths allowing the high controllability of the functionality and the thickness of the deposited layer. This thesis describes the functionalisation of a surface with pentafluorophenyl ester in a one-step process, reaching higher immobilization yield of bio-molecules than in a multi-step process. Also, the nature of pulsed-plasma polymers provides additional benefits such as irregular surfaces which make functionalities more accessible for subsequent reactions such as enzymatic modification as investigated in the fourth chapter. Finally, the last two chapters of this thesis deal with the occurrence of trapped free radicals within plasma polymers and their ability to induce graft-polymerisation of polymer brushes without prior attachment of initiators at the surface of a substrate. A comparison is drawn between a 'conventional' method using an initiator immobilised on the surface and trapped radicals to induce graft polymerisation. The influence of he nature of the monomer used during plasma polymerisation along with the conditions of deposition are studied with respect to the rate of subsequent graft polymerisation of styrene and the amount of trapped free radicals.
16
Zong, Mengmeng. "RAFT polymerisation in supercritical CO2". Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.537644.
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Parkes, Caroline Margaret. "'Living'/Controlled free-radical polymerisation". Thesis, University of Manchester, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488186.
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Wilson, Polly Alexandra. "Mechanistic Aspects of Polymerisation Catalysts". Thesis, University of East Anglia, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502560.
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The primary aim of this PhD was to further develop the mechanistic understanding of well-defined ansa-metallocene catalyst systems. SBI and IPCF ligated pre-catalyst materials activated by the trisarylborane, B(C6FSh, and tetrarylborate, [Ph3C][B(C6Fs)4] and [HNMe2Ph][B(C6Fs)4], co-catalysts were studied [SBI = Me2Si(1-lndh and IPCF = Me2C(Cp)(Flu)]. Counteranion influence on the end group distribution of poly(hex-l-ene) was investigated. lH NMR analysis of the polymer samples revealed an end group dependence both on the counteranion and the temperature at which the polymerisation was conducted. The outer-sphere ion pair (OSIP) [(SBI)Zr(CH2SiMe3t..·B(C6Fs)4l gave only vinylene end groups. While the inner-sphere ion pair (ISIP) (SBI)Zr(CH2SiMe3)(Il-Me)B(C6Fsh gave both vinylidene and vinylene end groups; the relative amount of the former was found to increase with temperature. A feasibility kinetic study into hex-l-ene polymerisations monitored by an on-line gel permeation chromatography (GPC) system was performed. The use of this instrumentation permitted data acquisition approximately every three minutes, giving data relating to molecular weight, polydispersity and conversion. A novel combined UV-visiblej1H NMR approach was employed to unequivocally characterise the absorption bands of different starting materials and catalyst active species. This enabled an extensive library to be constructed for SBI and IPCF bearing systems, which should provide an invaluable basis for future work in this area. Several products from the reactions of (IPCF)ZrMe2 with other materials were isolated and characterised by single crystal X-ray diffraction.
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Stephens, Gerard Groves. "Suspension polymerisation in oscillatory flow". Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627184.
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Yong, Tuck Mun. "Controlled polymerisation of methacrylate monomers". Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627136.
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Stevens, Wayne Jason. "Synthesis and polymerisation of macromonomers". Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/10474.
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Three novel macromonomer systems have been synthesised, characterised and free-radically polymerised. Both copolymerisations and homopolymerisations have been studied. The macromonomers are vinylbenzyl-terminated poly(methyl methacrylate) (PMMA), vinylbenzylterminated poly(butyl methacrylate) (PBMA) and vinylbenzoyl-terminated poly(ethylene oxide) (PEO). The PMMA (number average molar mass 1.4 x l03g!mol) and PBMA (number average molar mass 1.8 x 103 g!mol) macromonomers were synthesised by the same method. This involved the solution free-radical polymerisation of MMA or BMA in the presence of matched initiator and chain transfer agent (4,4' -azobis( 4-cyanovaleric acid) (ACV A) and thiogycollic acid (TGA), respectively). This produced monofunctional carboxyl-terminated prepolymers which were subsequently converted to acyl chloride-terminated prepolymers using oxalyl chloride. This was then combined with pre-synthesised vinylbenzylamine in the presence of triethylamine, to produce vinylbenzyl~terminated macromonomer. The PEO macromonomer (number average molar mass 2.1 x 103 g!mol) was produced by combining commercially available hydroxyl-terminated PEO with pre-synthesised 4-vinylbenzoyl chloride in the presence of triethylamine. All three macromonomers were each free-radically homopolymerised using 2,2' -azobis(isobutyronitrile) (AIBN) as the initiator. The PMMA and PEO macromonomers were studied in more detail in order to establish their solution polymerisation behaviours. This was achieved by carrying out several polymerisations using different initial macromonomer and initiator concentrations. Solution copolymerisations of all three macromonomers with maleic anhydride were also attempted in order to produce altemating single graft copolymers. Maleic anhydride was chosen as the comonomer on the understanding that stYrene produces altemating copolymers with it. The vinylbenzyl-terminated PBMA and PMMA macromonomers were shown to produce graft copolymers containing approximately a 0.5 : 0.5 molar ratio of macromonomer : maleic anhydride, regardless of the initial feed concentrations of the two. All polymers were characterised by gel permeation chromatography (GPC) and IH nuclear magnetic resonance spectroscopy eH NMR). Fourier transform infra-red spectroscopy (FT-IR) was used to characterise the carboxyl-terminated and acyl chloride-tenninated PMMA and PBMA prepolymers, as well as all three macromonomers. A selection ofPMMA graft copolymers were further characterised by solution viscometry and 13CNMR.
22
Yin, Xinning. "Magnesium ring-opening polymerisation catalysts". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:96a07187-2679-46ce-89ab-05586fa74c67.
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This Thesis describes the synthesis and characterisation of new magnesium borohydride, alkoxide and amide complexes, and their uses as catalysts for the ringopening polymerisation (ROP) of rac-, L-, D-, meso-lactide and ?-caprolactone. Chapter One introduces cyclic esters and possible mechanistic pathways leading to polyesters by ROP. Common techniques for polymer characterisation are described and an overview of ROP from an industrial perspective is also given. Chapter Two describes the synthesis and characterisation of a series of magnesium alkyl, halide, borohydride and alkoxide complexes supported by the 3-tert-butyl, 5- methyl tris(pyrazolyl)methane ligand. Computational analysis will be discussed to gain further understanding from the viewpoint of bonding and structures. Chapter Three describes the activities of magnesium borohydride and benzyloxide catalysts in the ROP of cyclic esters. Detailed mechanistic studies for the ROP of LA using a magnesium borohydride catalyst are discussed. Chapter Four describes the use of borate ester species as chain transfer agents in the immortal ROP of rac-LA and ?-CL. The effect of non-activated catalysts and borate ester species on the occurrence of transesterification side reactions is also discussed. Chapter Five describes the synthesis and characterisation of a series of magnesium amide, borohydride and halide complexes supported by the chiral bis(oxazolinylphenyl)amine ligand. The catalytic activities of the magnesium borohydride complex in the living and immortal ROP of LA are also discussed. Chapter Six contains experimental details and characterising data for the new complexes reported in this Thesis. CD Appendix contains .CIF files for all the new crystallographically-characterised complexes and .xyz files containing the coordinates of the geometrically optimised structures.
23
Newby, Thomas Edward. "Study of spontaneous polymerisation inhibition". Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/8728/.
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Spontaneous polymerisation is an unwanted reaction, prevented by inhibitor molecules. In order to observe the inhibition of spontaneous polymerisation by different molecules, a small scale dilatometry experiment was developed. This was used to screen structurally related molecules to 2-nitrophenol to determine what structural features give rise to inhibition properties. Compounds with an intramolecular hydrogen bond demonstrated more efficient inhibition of polymerisation. The product mixture of styrene inhibited by 2-nitrophenol was analysed to determine the reaction pathway. Column chromatography, MS and NMR were used to determine the structure of two intermediates, 2-aminophenol and a compound derived from a Diels Alder styrene initiator and 2-nitrophenol. The proposed intermediate, 2-nitrosophenol, was synthesised and its stability in styrene was determined. The products of reaction between 2-nitrosophenol and styrene at room temperature were proposed by comparing results with the reaction between styrene and nitrosobenzene. The main product of the inhibition by 2-nitrosophenol, was also determined to be 2-aminophenol, suggesting that 2-aminophenol formed from inhibition by 2-nitrophenol goes via 2-nitrosophenol. Other intermediates and products identified were also screened in the dilatometry setup. They show inhibition properties at high concentration, but at more realistic concentrations, they did not inhibit styrene polymerisation. An overall mechanism for the inhibition of styrene polymerisation by 2-nitrophenol, was proposed based on the data obtained.
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Potdevin, Alexander Philipp. "Kationische Polymerisation von flüssigkristallinen Monomeren". [S.l. : s.n.], 2006.
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Woecht, Inga. "Radikalische Polymerisation in ionischen Flüssigkeiten". Clausthal-Zellerfeld Papierflieger, 2009. http://d-nb.info/997007044/04.
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Hashim, Shahrir. "Drop mixing in suspension polymerisation". Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/34911.
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Suspension polymerisation is one of the major processes used to produce polymers. In this process, monomer is suspended as liquid droplets in a continuous water phase by mean of strong agitation and the presence of a suspending agent. As the suspension polymerisation proceeds, the viscosity of a monomer–polymer droplet increases with conversion. Hence, the physical behaviour of the droplet changes during the process. When new dispersible material is added to the existing suspension drops, the new material and existing drops can remain segregated for significant amounts of time. This will affect the properties of polymer products. The aim of this project was to study the behaviour of drop mixing when new material is added to the existing suspension polymerisation. This study concentrated on the effect of the dispersed phase viscosity on the drop mixing, but agitation intensity and surface stabilities were also important.
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Baqleh, Rami Daoud Yacoub. "Studies in post-metallocene polymerisation". Thesis, University of Manchester, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529232.
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Norström, Emelie. "Terpenes as renewable monomers for biobased materials". Thesis, KTH, Skolan för kemivetenskap (CHE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49875.
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With the ambition to decrease the utilization of fossil fuels, a development of those raw materials that today only are seen as waste products is necessary. One of those waste products is turpentine. Turpentine is the largest natural source of terpenes in the world today. The main components are the terpenes α-pinene, β-pinene and 3-carene. In this project, different polymerisation techniques have been evaluated to polymerise limonene with the aim to make a material out of the green raw material, turpentine. Limonene is a terpene that can be found in turpentine. It has a planar structure and should work as a model for other terpenes. Previous work on polymerising terpenes has focused on succeeding with performing polymerisations of terpenes utilizing the techniques of cationic polymerisation and radical polymerisation. However, this has been done without the aim to make a material out of the polymers. In this project, on the other hand, the main focus has been to obtain a polymer that can be used as a basis for a material. Techniques that have been applied are: radical polymerisation, cationic polymerisation and thiol-ene polymerisation. In this study, attempts to homopolymerise limonene and also copolymerise it with other synthetic monomers, such as styrene, have been performed with both radical polymerisation and cationic polymerisation. The procedure for the radical polymerisation has been conducted following the work by Sharma and Srivastava. [1] Even though several articles have been published about radical copolymerisations of limonene with other synthetic monomers, the radical polymerisations have not succeeded in this project. Further, the technique of thiol-ene chemistry has shown that limonene can be used in polymerisations; limonene reacts spontaneously with 2-mercaptoethyl ether forming a viscous polymer. The obtained polymers have been characterized with proton nuclear magnetic resonance(1H-NMR), size exclusion chromatography (SEC), matrix-assisted laser desorption ionization-time of flight mass spectroscopy (MALDI-TOF MS), differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy.
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Rives, Alain. "Approche cinetique des polymerisations rapides par une nouvelle technique de flux stoppe : la polymerisation cationique du styrene". Paris 6, 1994. http://www.theses.fr/1994PA066435.
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La polymerisation du styrene, amorcee par l'acide trifluoromethanesulfonique dans le dichloromethane, a ete reexaminee a l'aide d'un nouvel appareil a flux stoppe fonctionnant dans des conditions de tres haute purete et sur une large gamme de temperature. De plus, cet appareil a permis d'observer pour la premiere fois, la protonation des (e) 1,3-diphenylbut-1-ene et (z) 1,3-diphenylbut-1-ene par le meme acide dans le dichloromethane sous des conditions variees. Le monomere et le carbocation styryle ont ete suivis via leurs absorbances respectives a 292 et 343 nm. L'amorcage est tres rapide et la concentration en cations atteint un plateau dont l'etendue temporelle est fonction de la temperature. Dans les conditions utilisees (tfoh#o=0. 5-9. 10#-#3m, m#o/tfoh#o=0,05 a 20), la concentration en cations est si faible a temperature ambiante qu'elle est quasi inacessible a la mesure. A -65c, elle est cent fois plus grande et reste constante sur un intervalle de temps de plusieurs secondes. La terminaison a lieu en une minute ou plus. Un tel profil de variation de la concentration en cations est en accord avec une situation d'equilibre entre l'amorcage et une etape de deprotonation fortement dependante de la temperature. La vitesse initiale apparente d'amorcage suit une loi du premier ordre en monomere. Cette vitesse est d'ordre multiple en amorceur variant avec la temperature de 4. 5 a -65c a 3 a -20c. Ceci tend a demontrer l'existence d'agregats d'acide dont la reactivite augmente avec la taille. La consommation de monomere sur le plateau est d'ordre 1 ce qui conduit aux valeurs de k#p aux differentes temperatures: 10#3 (-65c) ; 2,9. 10#3 (-52c) ; 1,5. 10#4 (-33c) ; 3,7. 10#4 (-22c) ; 9. 10#4m#-#1. S#-#1(-10c) (e#p=40kj. Mol#-#1). La disparition des cations est tres rapide en presence de monomere. Elle se ralentit, lorsque celui-ci est entierement consomme, pour suivre une cinetique d'ordre 1. Les valeurs de k#t varient de 5. 10#-#2s#-#1 a -65c a 1,5 s#-#1 a +23c (e#t=25 kj. Mol#-#1). Cette etude, realisee a l'aide de l'appareil a flux stoppe, nous permet de proposer un mecanisme detaille en accord avec les observations cinetiques
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GOUASMI, ABDERRAHMANE. "Polymerisation spontanee de la 4-vinylpyridine. Synthese de polymeres et copolymeres. Etude du mecanisme de polymerisation". Strasbourg 1, 1998. http://www.theses.fr/1998STR13253.
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Dans le premier chapitre, nous etudions la reaction de quaternisation de la pyridine comme molecule modele, et l'effet sur cette reaction des parametres tels que la nature de l'alkylant, la nature du solvant et la temperature. L'etude montre que les cinetiques de quaternisation suivent la loi d'arrhenuis, et sont favorises par la polarite du milieu et par le caractere partant du contre-ion (provenant de l'alkylant). Dans le chapitre 2, nous etudions la synthese de poly(4-vinylpyridine)n-altylee. Des vitesses de quaternisation elevees, causees par un milieu polaire donnent des masses molaires elevees des polysels correspondants. Nous avons pu montrer que la synthese de copolymeres statistiques et a-blocs est possible. Par contre, le systeme n'est pas vivant, cause probablement par une reaction de terminaison. Le dernier chapitre est consacre au mecanisme reactionnel de la polymerisation spontanee de sel-monomere : le methylsulfate de n-methyl(-4-vinylpyridinium). On montre clairement que le contre-ion halogene contribue plus a l'amorcage que la pyridine, en adoptant une methode originale. On prouve encore que la reaction de polymerisation n'est pas anionique mais plutot procede par transfert concerte. Un mecanisme a ete propose.
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Khodabakhshi, Khosrow. "Anionic polymarisation of caprolactam : an approach to optimising thr polymerisation condition to be used in the jetting process". Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8369.
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The main aim of this project was to investigate the possibility of manufacturing 3D parts of polyamide (nylon or PA) 6 by inkjetting its monomer caprolactam (CL). The principle of this process was similar to the other rapid prototype (RP) and rapid manufacturing (RM) processes in which a 3D part is manufactured by layer on layer deposition of material. PA6 was used as the thermoplastic polymer in this work because of its good properties and also because PA6 can be produced by heating its monomer (i.e. plus catalyst and activator) in a short time. Two polymerisation mixtures of CL-catalyst (mixture A) and CL-activator (mixture B) are intended to be jetted separately using conventional jetting heads and polymerise shortly after heating. Anionic polymerisation of CL (APCL) was investigated in the bulk and on a smaller scale. Sodium caprolactamate (CLNa and C10) and caprolactam magnesium bromide (CLMgBr) were used as catalysts and N-acetylcaprolactam (ACL) and a di-functional activator (C20) were used as activators. The influence of polymerisation conditions was investigated and optimised. These were catalyst-activator concentration, polymerisation temperature and the influence of the polymerisation atmosphere. The physical properties (monomer conversion, crystallinity, and viscosity average molecular weight) of PA6 samples produced using each catalyst-activator combinations were measured and compared. Small scale polymerisation was carried out using a hotplate, by hot stage microscopy and using differential scanning calorimetry (DSC). The influence of heating strategy on small scale polymerisation was studied using DSC. The polymerisation mixture compositions were characterised using rheometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and optical microscopy to investigate their suitability in jetting for using the available jetting heads. It was shown that the combination of CLMgBr-ACL resulted in fast polymerisation which was not sensitive to moisture. The C10-C20 combination resulted in fast polymerisation with the best properties in a protected environment (nitrogen); however, the polymerisation was affected by moisture in air and the properties of polymer produced and rate of polymerisation decreased in air. Polymers produced using CLNa-ACL had the poorest properties and polymerisation did not occur in air. Material characterisation showed that micro-crystals of CLMgBr existed in CLMgBr-CL mixture at the jetting temperature (80oC) which were too large to be jetted. However, the mixture of C10 in CL could be partially jetted. The activator mixtures had similar properties to CL and were easily jetted. Drop on drop polymerisation was carried out by dripping droplets of mixtures A and B (at 80oC) on top of each other on a hotplate at the polymerisation temperature. Small scale polymerisation in a DSC showed that the monomer conversion increased with increase in polymerisation temperature from 140oC to 180oC and decreased from 180oC to 200oC. The crystallinity of the polymer produced in the DSC decreased with increase in polymerisation temperature. Hot stage microscopy produced evidence for simultaneous polymerisation and crystallisation processes on heating. Small scale polymerisation in an oven and analysed by DSC showed that increasing catalystactivator concentration resulted in increasing monomer conversion and decrease in crystallinity. Monomer conversion also increased with increase in polymerisation temperature and polymerisation time. Comparison between small scale and bulk polymerisations shows a good agreement between the two polymerisation rates. This shows that the polymerisation mechanism did not change significantly when the quantity of materials was reduced to less than 20mg. Finally, the polymerisation was carried out in a DSC after jetting C10-CL and C20-CL mixtures into a DSC pan using a jetting system, which was made in another work.
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Khelfallah, Nawel Souad. "Kontrollierte radikalische Polymerisation von polaren Monomeren". [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=971304750.
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Brocken, Laurens. "Polymerisation in flow and solid state". Thesis, Durham University, 2016. http://etheses.dur.ac.uk/11918/.
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The aim of this thesis was to develop and facilitate new approaches to polymer synthesis. The chosen tools for this task were flow chemistry and topochemical polymerisation. Flow chemistry has proven its strength in the past and is a technique suitable for performing synthesis at scale. Three areas were explored in this thesis. In the first results chapter the free radical polymerisation of aqueous solution of acrylic acid (7) has been studied using a continuous flow reactor to quickly screen reaction parameters such as temperature, residence time, monomer- and initiator concentration. The experimental data sets produced established a theoretical basis for conducting scale up processes to efficiently produce larger quantities of poly(acrylic acid) (8) delivered with good control over the molecular weight and dispersity. The data sets were used to study the ability to synthesise polymers on demand. The developed methodology to synthesise aqueous soluble polymers in flow, possessing a variety of molecular weights and dispersities have been achieved. However, full conversion was hard to achieve without increasing the dispersity and purification was therefore necessary. The second results chapter studied the direct purification to obtain purified polymer under one hour. This opened up a new way to synthesise and isolate polymers. Performing a free radical polymerisation in flow does not result in the control over tacticity of the polymerisation. The third results chapter studied the synthesis of polymers via topochemical polymerisation and the advantages it can add to general polymer synthesis.
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James, M. I. "Emulsion polymerisation of vinylidene chloride copolymers". Thesis, Lancaster University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235213.
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Woods, Rebecca J. "Bidentate nitrogen ligands for olefin polymerisation". Thesis, University of Manchester, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488051.
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Arbaoui, Abdessamad. "New complexes for ε-caprolactone polymerisation". Thesis, University of East Anglia, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502042.
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The present study deals with the synthesis and characterisation of a number of new complexes incorporating main group and transition metals. The catalytic behaviour of these complexes for the ring opening polymerisation of ε-caprolactone is discussed. Iron and alkali metals complexes (1 - 8) bearing calixarene ligands were obtained by reacting [MFe(Or-Bu)₃(THF)]₂ (M = Na, K) with p-rer/-butylcalix[4, 6 and 8]arene (L¹H₄,L² H₆ and L³ H₈ respectively), p-ferr-butylhexahomotrioxacalix[3]arene (L⁴H₃) or p-tert-butyltetrahomodioxacalix[6]arene (L⁵H₆). Treatment of L⁵H₆ with ZnEt₂ afforded the hexanuclear complex [L⁵Zn₆Et⁴(OEt)₂(CH₃CN)₄] (9.4(CH₃CN)).Reaction of AIR₃ (R = Me, Et) with the macrocyclic Schiff base ligand L⁶H₂ afforded the complexes (L⁶A1R₂)₂ (R = Me (10), Et (11)), L⁷H₂(AlMe₂)₂ (12) and L⁷H₂(AlMe₂)₄ (13) respectively. Complexes 12 and 13 were obtained via methyl transfer to imine moieties of the macrocycle framework. The acyclic analogues of complexes 12 and 13 were synthesised for catalytic comparison, along with a series of dinuclear zinc complexes bearing Schiff base ligands, obtained by metal template synthesis.
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Gemici, Hesna. "Water soluble polymers by RAFT polymerisation". Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507717.
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Achi, S. S. "Bulk polymerisation of some azo-monomers". Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371461.
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O'Donnell, John Patrick. "Catalytic chain transfer in emulsion polymerisation". Thesis, University of Warwick, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300718.
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Fraser, Kathryn. "An investigation of nitroxide-mediated polymerisation". Thesis, University of York, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288036.
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Court, Richard W. "Organic polymerisation in the solar system". Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427735.
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Overton, Tina Lyn. "Characterisation of Cr-silica polymerisation catalysts". Thesis, University of Lincoln, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278042.
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Wiggins, Christopher John. "NMR imaging studies of polymerisation processing". Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388340.
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Bray, Caroline. "Aqueous RAFT polymerisation of acrylamide monomers". Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/111296/.
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The challenge of this project was to control the polymerisation of acrylamide monomers, particularly sodium 2-acrylamido-2-methylpropane sulfonate (Lubrizol trademark, AMPS®2405), via reversible addition-fragmentation chain transfer (RAFT) polymerisation in aqueous solution. AMPS® based polymers are employed in a wide range of applications (e.g. medical, paint, oil recovery and water treatment), and are typically obtained via conventional radical polymerisation. Here, the use of the RAFT process to control the polymerisation of AMPS®2405 was reported, and well-defined polymeric architectures were obtained compared to materials obtained via free radical polymerisation (FRP). The chain transfer agent (CTA) of choice for this project was initially DDMAT (CTA-A, Z-group is C12H25), and a water soluble CTA synthesised by the Lubrizol corporation (USA) in tonne-scale. DDMAT is known to form aggregates in water ([CAC]DDMAT =0.005 M) and this is likely to disrupt the RAFT mechanism and consequently diminish the control over the polymerisation. To overcome this problem a chain transfer agent with a shorter alkyl chain (BDMAT, Z-group is C4H9) was used for comparison with DDMAT. The polymerisation of AMPS®2405 monomer was optimised, as discussed in CHAPTER 2, in aqueous solution using either DDMAT or BDMAT as a chain transfer agent. These conditions were found to be universal to other water soluble acrylamide monomers (N,N-dimethylacrylamide, N-hydroxyethyl acrylamide and 4-acryloylmorpholine). More complex architectures were designed, as described in CHAPTER 3, exploiting the high chain end fidelity and chain extensions. A small library of diblock copolymers using various comonomers (N,N-dimethylacrylamide, N-hydroxyethyl acrylamide, 4-acryloylmorpholine, acrylic acid and acrylamide) were first synthesised. The synthesis of star polymers using the arm first approach was further studied, and well-defined multiblock star copolymers were obtained by RAFT polymerisation. These structures synthesised were characterised, as discussed in CHAPTER 4, using diverse techniques (e.g. SAXS, DLS, SEC with triple detection and AFM). While copolymers prepared from AMPS®2405 can be used in numerous applications, the focus of this thesis, as discussed in CHAPTER 5, was to study their benefit as heparin-mimicking polymers.
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Hancock, Stuart. "Preparation of initiators for sustainable polymerisation". Thesis, University of Bath, 2013. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577743.
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Current plastics are mostly derived from petrochemical sources, as it is a finite resource renewable replacements are sought after. Polymers derived from cyclic esters such as; lactide, valerolactone and caprolactone are of interest. An industrially viable method of producing stereocontrolled polylactide (PLA) from rac-lactide is desired. Previous work on poly(cyclic esters) is overviewed in chapter 1 with an emphasis upon PLA. Chapter 2 reports the coordination of Ti(OiPr)4 to homo/piperazine bridged bis(phenol) (salan) ligands. Under ambient conditions bimetallic structures were produced and a steric dependent equilibrium system is discussed. Forcing conditions resulted in monometallic homopiperazine salan complexes. Their application for the ring-opening-polymerisation (ROP) of rac-lactide is investigated. Homo/piperazine salan titanium catecholates were synthesised and their cytotoxicity investigated by collaborators. Chapter 3 details the synthesis of monometallic homopiperazine salan zirconium/hafnium isopropoxide complexes. Their utility for the ROP of rac-lactide in solution and solvent free systems are discussed. Bimetallic or tetrametallic solid state structures from attempts to coordinate Zr(IV)/Hf(IV) metals to piperazine salan ligands are also discussed. Chapter 4 discusses the complexation of AlMe3 with homopiperazine salan ligands. The resulting monometallic complexes were inactive for the ROP of lactide. Benzyl alcohol derivatives were synthesised and trialled for solvent free ROP of rac-lactide, δ-valerolactone, ε-caprolactone. Co-polymerisations were investigated and a tri-block polymer of poly(ε-caprolactone/δ-valerolactone/rac-lactide) was prepared. Chapter 5, trans-1,4-DACH salen ligands were synthesised and investigated as ligands with Al(III), Ti(IV), Zr(IV), and Zn(II) metal centres. Bimetallic Al(III) and Ti(IV) structures were characterised and trialled for the ROP of rac-lactide. Isotactic PLA was reported for aluminium complexes, dependent upon phenoxy substituents, and these polymerisations were shown to be immortal in nature. Chapter 6 details the synthesis of trans-1,2-DACH salalen ligands which were complexed to AlMe3, these initiators were investigated for the solution ROP of rac-lactide. The further synthesis of benzyloxy derivatives is also reported and they were utilised for solution and solvent free polymerisations of rac-lactide. The initiator’s behaviour is discussed with respect to varying amine and imine groups.
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Ogilvy, Norman. "Vinyl chloride precipitation polymerisation : charge effects". Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/11229.
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Baghurst, Rebecca E. "Ligand frameworks for olefin polymerisation catalysts". Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/55566/.
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The synthesis and characterisation of ligands which have the potential to support olefin polymerisation catalysts has been investigated. The syntheses are presented of a range of mixed tertiary amine/alkoxide donor ligands formed by the ring opening of (+/-)-3,3-dimethyl-l,2-epoxybutane by linear and cyclic amines, including N,N'-c/nnethylethylenediamine, 1,4-diazacycloheptane, 1,4-diazacyclohexane, monoazacyclohexane, 1,4,7,10-tetraazacyclododecane and 1,4,7-triazacyclononane. A series of ligands derived from rraw5-l,2-uiaminocyclohexane, 1,4-diazacyclohexane and 1,4-diazacycloheptane has also been synthesised via substitution chemistry. The coordination chemistry of 7V A'-bis(2-hydroxy-3,3-dimethylbutyl)-1,4-diazacycloheptane has been investigated. Monometallic complexes with nickel and aluminium have been characterised. Two examples of bimetallic titanium complexes with Ar,7-bis(2-hydroxy-3,3-dimemylbutyl)-l,4-diazacycloheptan synthesised from titanium ethoxide and titanium isopropoxide are also reported the structure of each has been determined by X-ray crystallography. A discussion of how the choice of titanium alkoxide starting material affects the outcome of the ligand substitution chemistry is presented. The syntheses of related complexes containing the more flexible ligand N,7V-6w(2-hydroxy-3,3-& in conjunction with zirconium and titanium are presented and the crystal structures reported. Furthermore, complexes of the macrocyclic ligands Ar,A',A"-(2-hydroxy- 3,3-dimethylbutyl)- 1,4,7-triazacyclononane with titanium and N,N',N",N'"-(2- hydroxy-3,3-dimethylbutyl)-1,4,7,10-tetraazacyclododecane with zirconium are reported. The activity of selected complexes towards olefins including ethylene and 1-hexene using methylaluminoxane as an activator has been determined. Investigation into the nature of the reaction products has been undertaken using gel permeation chromatography and GC-MS. In general the complexes synthesized during the course of this study show low activities towards olefin polymerisation.
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Castillejo, Antonio Guerrero. "Zinc-promoted carbocationic polymerisation of isobutenes". Thesis, University of East Anglia, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429825.
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The carbocationic polymerisation of polyisobutenes initiated by zinc-based Lewis acids has been investigated. Polyisobutenes are important materials that find their applications depending on the molecular weight. Thus, the production of butyl rubber ( Mw ~500,000) by the copolymerisation of isobutene (ill) with isoprene (IP) is an important industrial process. Commercially, polymerisation is initiated by protons generated using an AICh / H20 slurry in chloromethane solvent at low temperatures (ca. -100°C). Incorporation of IP is typically of the order of 1-2%. However, under such conditions isoprene acts as a powerful retardant, and both polymer molecular weight and polymer yield decrease steeply with increasing [IP] in the monomer feed. A system based on Zn(C~5h and an alkyl halide that produces copolymers with high molecular weights and increased isoprene incorporation have been found. Hence with increased main chain unsaturation, which is desirable to achieve more efficient crosslinking and improved compatibility with other unsaturated polymer materials. Studying the reactivity of this Lewis acid we could isolated a non-nucleophilic zincate and proved the capability of generating carbocations. On the other hand, the low reaction rate in covulcanisation found for Butyl rubber could be circumvented by polymerising isobutene with a small fraction of a comonomer different to IP that led to a search for new materials. Hence, polymers containing functionalities such as unsaturations of potentially higher reactivity than internal double bonds, phenylchlorinated units or pendant trimethylsilyl groups have been incorporated into the polymer chain. Finally, a system based on alkylzinc halides and alkyl halides provides polyisobutenes of a wide range of molecular weights ( Mn = 10,000- 150,000) at temperatures between -78 °C and +35 °C. These systems are the first that generates polyisobutenes with high ratios of teoninal double bonds at high temperatures that do not rely on transition metal components or complex noncoordinating anions.
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Unruangsri, Junjuda. "Group 2 ring-opening polymerisation catalysts". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:9296a84f-2639-48e9-9ed6-68ee1a61859e.
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This Thesis describes the synthesis and characterisation of new Group 2 tetrahydroborate, alkoxide and organohydroborate complexes and their uses as catalysts for the living ROP and immortal ring-opening polymerisation (iROP) of ε- caprolactone and rac-lactide. Chapter One introduces cyclic esters and possible mechanistic pathways leading to polyesters by ROP. Living and immortal ROP, including their kinetic characteristics are discussed. An overview of ROP from an industrial perspective is also given. Chapter Two describes the synthesis and characterisation of a new series of Group 2 tetrahydroborate complexes supported by a 3-methyl, 5-tert-butyl tris(pyrazolyl)hydroborate ligand. Their activities towards the ROP of ε-caprolactone are presented. Detailed mechanistic studies using spectroscopic techniques are discussed and a new mechanism is proposed. Chapter Three describes the ROP of rac-lactide using the Group 2 tetrahydroborate complexes introduced in Chapter Two, including their mechanistic studies. Chapter Four introduces the new immortal ROP using trialkyl borate and organoborane derivatives as chain-transfer agents (CTAs). The immortal ROP of ε- caprolactone and rac-lactide using Group 2 initiators with trialkyl borates/organoboranes as CTAs from either in situ generation or external addition is discussed. Possible immortal ROP pathways using this new class of CTAs are illustrated. Chapter Five details the synthesis and characterisation of a new series of Group 2 organohydroborate complexes. The ε-caprolactone and rac-lactide ROP activity shown by the complexes presented is discussed and compared with those obtained from the corresponding tetrahydroborate analogues. Chapter Six contains experimental details and characterising data for the new complexes reported in this Thesis. CD Appendix contains .CIF files for all the new crystallographically-characterised complexes.
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Oseland, Elizabeth E. "Electrochemical studies of interfacial polymerisation processes". Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/89097/.
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This thesis describes how electrochemical analytical techniques have been used to understand some of the physicochemical processes that underpin interfacial polymerisation reactions. A few of the reaction systems studied are currently used in the agrichemical industry for the formation of microcapsules for active ingredient encapsulation. Interfacial processes that take place at the oil-water interface of an epoxy-amine emulsion polymerisation system have been studied. Time-lapse microscopy of epoxide droplets in water or aqueous amine solutions has shown the effect of temperature on droplet dissolution and interfacial polymerisation. Quantitative kinetic data were extracted. A combination of microelectrochemical measurements at expanding droplets and finite element modelling has been used to measure the fast transfer of amine out of an organic phase comprised of epoxide and amine into the aqueous phase. Electrochemical impedance spectroscopy was used to monitor a growing poly(urea) film formed at a model liquid/liquid interface at the tip of a micropipette. A simple circuit diagram was used to model the liquid/liquid interface before and after film formation, highlighting how the presence of the film will increase interfacial resistance and decrease interfacial capacitance. Poly(urea) formation under a range of different reaction conditions was investigated using a combination of impedance versus time measurements and scanning electron microscopy. Finally, the polymerisation of acrylamide monomers at a solid/liquid interface for discrete surface functionalisation was examined using a combination of scanning electron microscopy and atomic force microscopy.