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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Synthesis, characterisation and properties of some well-defined comb graft copolymers

Rizmi, Abdul Cassim Mohamed January 1997 (has links)
This thesis describes studies directed to the ring opening metathesis polymerisation of macromonomers and mesogenic monomers to produce graft copolymers and side chain liquid crystalline polymers respectively. The necessary background information relevant to the work described in this thesis is presented in chapter-1 and consists of four sections; namely, descriptions of metathesis polymerisation, anionic polymerisation, synthesis of graft copolymers and synthesis of side chain liquid crystalline polymers. The synthesis of the end capping reagent exo-5-norbomene-2- carbonyl chloride is described in chapter-2. The synthesis and characterisation of exo- 5-norbomene-2-poly(styrylcarboxylate) macromonomers by living anionic polymerisation is discussed in chapter-3. Chapter-4 reports the synthesis, characterisation and properties of graft copolymers prepared by ring opening metathesis polymerisation of exo-5-norbomene-2-poly(styrylcarboxylate) macromonomers. Chapters-5 describes the synthesis of the mesogenic monomer; (5)- (-)-2-methylbutyl-4-(4-(l 0-(3-cyclopentenylmethoxy) decyloxy) phenylcarbonyloxy) benzoate, suitable for ring opening metathesis polymerisation to produce side chain liquid crystalline polymer. The attempted synthesis of side chain liquid crystalline polymer by ring opening metathesis polymerisation of the mesogenic monomer; (5)-(- )-2-methylbutyl-4-(4-( 10-(3 -cyclopentenylmethoxy) decyloxy) phenylcarbonyloxy) benzoate is reported in chapter-6. Finally chapter-7 summarises the conclusions and makes some suggestions for future work.
2

Peroxide Curable Butyl Rubber Derivatives

Siva Shanmugam, Karthik Vikram 06 July 2012 (has links)
Isobutylene-rich elastomers bearing functional groups that engage N-arylmaleimides in C-H bond addition and/or alternating copolymerization are described. While inactive to cross-linking when treated at high temperature with peroxide alone, these co-curing elastomers can be cross-linked substantially when combined with bis-maleimide coagents such as N,N’-m-phenylene dimaleimide (BMI). Poly(isobutylene-co-isoprene) (IIR) samples containing relatively high amounts of residual isoprene unsaturation are shown to provide relatively low coagent cure reactivity, whereas IIR derivatives bearing pendant polyether or vinyl ether functionality are shown to provide exceptional cross-linking rates and extents when treated with identical BMI formulations. The design of such co-curing elastomers is discussed, along with the physical properties of the resulting vulcanizates. Isobutylene rich elastomers bearing oligomerizable (C=C) functional groups, macromonomers, that are activated in the presence of free-radical initiators are described. The criteria for determining the macromonomers that are best suited for preparing thermosets of IIR is discussed. While IIR derivatives bearing pendant acrylic, styrenic and maleimide functionality are shown to provide exceptional cross-linking rates and extents, they are also shown to suffer from instability in the absence of peroxide. IIR carrying pendant methacrylic and itaconate functionality are shown to provide a good balance of cure rates and stability. Nitroxyl based radical trap that provides scorch protection to the macromonomers while regenerating the cure extent is discussed. Functional macromonomer derivatives of IIR bearing containing multi-functional pendant groups are discussed. IIR derivatives with itaconate and low amounts of BHT pendant groups is shown to act as bound anti-oxidant while IIR containing pendant fluoro groups are shown to have reduced surface energy. Ionic coagents are used to cross-link IIR containing itaconate pendant groups and their physical properties are discussed. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-07-06 11:20:56.915
3

Smart polymeric materials by ring-opening metathesis polymerization / Préparation de matériaux polymères submicroniques "intelligents" par ROMP

Neqal, Mehdi 11 September 2017 (has links)
Ce travail de thèse consiste à combattre le développement microbien des réservoirs de carburant aéronautiques dont le métabolisme entraine la production d’acides organiques susceptibles de corroder les parois métalliques des réservoirs. Des substances biocides sont habituellement utilisées pour éliminer les populations microbiennes. Ces substances peuvent être des composés organiques ou bien de manière plus courante du chrome (VI) sous forme de revêtement à la surface des parois afin de créer une couche passive et d’empêcher la corrosion chimique. Cependant, le chrome appartient à la catégorie des substances cancérogènes, mutagènes et reprotoxiques et se trouve maintenant soumis à restriction par la réglementation européenne Registration, Evaluation and Authorization of Chemicals (REACh). Pour remplacer les systèmes en place, le choix s’est porté sur la préparation de particules polymères pH-sensibles capables de libérer une molécule biocide en présence de microorganismes. De telles particules sont obtenues par copolymérisation par métathèse de cyclo-oléfines (ROMP) de norbornène avec un macromonomère linéaire de polyglycidol α-norbornenyl. Ce dernier permet d’une part la stabilisation des particules et d’autre part la multifonctionnalisation de l’objet par des molécules de biocide. Celles-ci sont introduites sur la chaîne de polyglycidol via un lien imine pH-sensible par substitution des fonctions hydroxyle par des entités dodécylamine. La libération du biocide à un pH inférieur à 7 a été validée ainsi que les capacités de ces particules à lutter contre des microorganismes tel que Hormoconis resinae souche identifiée comme se développant dans les réservoirs d’avions. Dans une dernière étape, les particules fonctionnalisées dodécylamine ont été incorporées dans un revêtement usuel en aéronautique et la capacité des particules à ne pas altérer la résistance du revêtement de base à des conditions de corrosion extrêmes a permis de vérifier leur applicabilité dans ce domaine. / The aim of this Thesis work was to address the issue of microbial contamination inside fuel tanks. Microorganisms induce the chemical corrosion of airplane tank walls due to their production of organic acids. Biocide compounds are typically used to inhibit these microorganisms, either in the form of organic small molecules, or most commonly as chromium-based coatings on the walls to hinder chemical corrosion. Organic biocides need to be replenished regularly, while chromium is a particularly dangerous compound targeted by the European Registration, Evaluation and Authorization of Chemicals (REACh) legislation due to its carcinogenic nature. A replacement approach selected for this project was the development of a smart system of multifunctional polymeric particles synthesized by dispersion ROMP, which can deliver a biocide following an acidic trigger due to the presence of microorganisms. The polymerization utilized a linear α-norbornenyl-polyglycidol macromonomer as a reactive surfactant. The hydroxyl-rich polyglycidol backbone of the macromonomer was beneficial for the conjugation of dodecylamine through a pH-sensitive imine bond and permitted the preparation of highly functionalized bioactive particles. A proof of concept for the pH sensitivity of the system was provided and the antifungal efficacy of the biocide-functionalized macromonomer and particles was verified. The particles were also integrated in a coating formulation to simulate their application on tank walls. The qualities of the original coating were preserved even after prolonged exposure to corrosive conditions, making this system viable for its foreseen application.
4

Synthesis and characterization of two novel urethane macromonomers and their methacrylic/urethane graft copolymers

Alshuiref, Abubaker 03 1900 (has links)
Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Polymethacrylates are well known adhesives and can carry specific functionality, but have the disadvantage that their flexible backbones impart limited thermal stability and mechanical strength. Polyurethanes (PUs) are finding increasing application and use in many industries due to their advantageous properties, such as a wide range of flexibility combined with toughness, high chemical resistance and excellent weatherability. PUs do however have some disadvantages, for instance, PU is considered an expensive polymer, especially when considered for solvent based adhesives. the focus of this study was to consider a largely unstudied area of PU chemistry, namely combining PUs with polymethacrylates. Two types of linear urethane macromers (UMs) UM1 and UM2 were synthesized by the polyaddition polymerization of 4,4'-methylenediphenyl diisocyanate (MDI) with ethylene glycol (EG), and MDI with neopentylglycol (NPG), via a pre-polymer method, followed by termination with 2-hydroxy ethylacrylate (2-HEA) and methanol (MeOH) to yield UMs having specific urethane chain lengths, and which have to be predominantly monofunctional. Structural identification of the UMs was verified by MALDI-TOF-MS, FTIR, 13C-NMR and 1HNMR spectroscopy.Various percentages of the respective UMs (0_55 wt % of methacrylate monomers) were then incorporated into polymethyl methacrylate (PMMA) and poly n-butyl methacrylate (PnBMA) backbones via solution free-radical copolymerization. The resulting methyl methacrylate-g-urethane and n-butyl methacrylate-g-urethane copolymers were characterized by 1H-NMR,13C-NMR, FTIR, SEC with double detectors (UV and RI), light scattering, UV-Vis, HPLC, TGA, DSC, DMA and TEM. Weight percentages of UM incorporated into the methyl methacrylate-g-urethane copolymers were calculated using FTIR, UV-Vis and 1H-NMR techniques. Phase separation which occurred between the urethane segment and methacrylate segment in the graft copolymerization products was investigated by DMA, DSC and TEM analysis. Microphase separation occurred in all PMMA-g-UM1 and PnBMA-g-UM1 copolymers: two glass transitions temperatures corresponding to the PMMA or PnBMA and UM1 fractions, respectively, were observed. On the other hand, DMA and DSC results showed that in most graft copolymer products the two respective component parts PMMA-g-UM2 or PnBMA-g- UM2 were compatible, because only one Tg was observed. Two glass transitions occurred for PMMA or PnBMA and UM2 when the amount of UM was increased to 55 wt % during copolymerization and microphase separation was evident in DSC, DMA and TEM measurements. Thermal stability and storage modulus (stiffness) of all the synthesized PMMA-g-urethane and PnBMA-g-urethane copolymers increased as the concentration of urethane macromonomer in the copolymerization feed increased, as confirmed in TGA and DMA results. The surface and adhesive properties of the synthesized graft copolymer were studied by measuring the static contact angle and peel strength. Adhesion increased as the content of UMs increased in the graft copolymer. The graft copolymers prepared using a high UM2 feed for both PMMA and PnBMA showed improved in adhesion compared to the pure methacrylate polymers. The adhesion was better for both leather and for vinyl. / AFRIKAANSE OPSOMMING: Polimetakrilate is bekende kleefstowwe. Hulle het egter die tekortkoming dat hulle buigbare ruggraat beperkte termiese en meganiese stabliteit besit. Poliuretane (PUs) word deesdae al hoe meer gebruik in baie nywerhede as gevolg van hulle baie voordele, insluitend hul wye buigsaamheid tesame met sterkte, hoë chemiese weerstand en uitstekende weerbaarheid. PUs het egter ’n paar nadele: hulle is baie duur, veral wanneer hulle gebruik word in oplosmiddel-gebaseerde kleefstowwe. Die doel van hierdie studie is om die kombinering van PUs met polimetakrilate te bestudeer, 'n onderwerp wat tot dusver baie min aandag-getrek het. Twee tipes liniêre uretaanmakromere (UMs), UM1 en UM2, is gesintetiseer deur gebruik te maak van poliaddisiepolimerisasie van 4,4'-metileendifeniel diisosianaat (MDI) met etileenglikol (EG), en MDI met neopentielglikol (NPG), via ‘n prepolimeermetode, gevolg deur terminering met 2-hidroksiëtielakrilaat (2-HEA) en metanol (MeOH). Die produk hiervan is UMs met spesifieke kettinglengtes (hoofsaaklik monofunksioneel). Die samestelling van die UMs is met behulp van die volgende gevorderde analitiese tegnieke bepaal: MALDI-TOFMS, FTIR, 13C-NMR en 1H-NMR. Verskillende hoeveelhede van die UMs (0_55 gewIing% metakrilaatmonomere) is dan in die polimetielmetakrilaat (PMMA) en poli-n-butielmetakrilaat (PnBMA) ruggrate geïnkorporeer deur middel van oplossing-vryradikaalpolimerisasie. Die samestelling van die kopolimeerprodukte, metiel-metakrilaat-g-uretaan en n-butiel-metakrilaat-g-uretaan, is met behulp van die volgende gevorderde analitiese tegnieke bepaal: 1H-NMR, 13C-NMR, FTIR, SEC met dubbele detektors (UV en RI), ligverstrooiing UV-Vis, HPLC, TGA, DSC, DMA en TEM. Die hoeveelheid UM geïnkorporeer in die metielmetakrilaat-g-uretaan kopolimere is bereken deur gebruik te maak van FTIR, UV-Vis en 1H-NMR data. Die faseskeiding wat plaasgevind het tussen die uretaansegment en die metakrilaatsegment in die produkte van die entpolimerisasie is met behulp van DMA, DSC en TEM ondersoek. In alle PMMA-g-UM1 en PnBMA-g-UM1 kopolimere het mikrofaseskeiding plaasgevind: twee verskillende glasoorgangstemperature vir die PMMA of PnBMA en UM1 fraksies is waargeneem. Hierteenoor het DMA en DSC resultate getoon dat in die meeste entkopolimeerprodukte (PMMA-g-UM2 of PnBMA-g-UM2) was die twee komponente verenigbaar, aangesien net een Tg waargeneem is. In die geval van die kopolimere waar die hoeveelheid UM in die kopolimerisasiereaksies tot 55 gew% verhoog is, is twee glasoorgangstemperature vir PMMA of PnBMA, en UM2 waargeneem. Mikrofaseskeiding is met behulp van DSC, DMA en TEM bewys. Termiese stabiliteit en stoormodulus (styfheid) van alle gesintetiseerde PMMA-g uretaan en PnBMA-g-uretaan kopolimere het toegeneem namate die uretaankonsentrasie in die kopolimerisasiereaksie toegeneem het soos deur middel van TGA en DMA resultate bewys is. Die oppervlakte- en kleefeienskappe van die bereide entkopolimere is bestudeer deur die statiese-kontakhoek en skilkrag te meet. Adhesie het toegeneem namate die UMinhoud toegeneem het. Die entkopolimere berei met hoë PMMA en PnBMA inhoud het uiteindelik beter adhesie getoon as die suiwer metakrilaatpolimere. Die adhesie was beter vir beide leer en viniel.
5

Synthèse et applications de structures hyperramifiées biocompatibles / Synthesis and applications of biocompatibles hyperbranched structures

Winninger, Jérémy 19 December 2014 (has links)
L’objectif de ce travail a été de procéder au design de nouvelles structures hyperramifiées en procédant à la synthèse de polymères à base de glycidol utilisables dans l’élaboration de copolymères biodégradables, de macromonomères fonctionnels et de nanocomposites magnétiques biocompatibles. Une première partie de ces travaux s’est intéressée, à la synthèse de macromonomères hyperramifiés amorcés par l’hydroxyéthyle méthacrylate (HEMA), l’hydroxyéthyle acrylate (HEA) et le polyéthylène glycol méthacrylate (PEGMA), par polymérisation anionique, anionique coordinée ou cationique du glycidol. La synthèse de macromonomères poly(ε-caprolactone) en présence de différents systèmes catalytiques et amorceurs a également été investiguée. Cette partie se termine par la synthèse de dendrigrafts issus de la polymérisation de ces macromonomères, par voie radicalaire classique ou contrôlée (RAFT/ATRP). La seconde partie de ce travail a été consacrée à la synthèse de copolymères hyperramifiés biocompatibles obtenus par copolymérisation statistique du glycidol en présence d’ε-caprolactone, en vu de l’obtention de copolymères hydrolysables. L’impact de la structure sur les propriétés physico-chimiques des copolymères obtenus a été étudié. Enfin, le caractère biodégradable de ces polymères a été investigué à travers différents tests de dégradation enzymatique. Enfin, ce travail s’est focalisé sur l’élaboration de nanocomposites magnétiques biocompatibles par la synthèse de nanoparticules magnétiques, puis l’immobilisation de polymères linéaires ou hyperramifiés à leur surface selon différentes méthodes de greffage chimique. / The aim of this work was to proceed to the design of new hyperbranched structures through the synthesis of glycidol-based polymers which can be used in the development of biodegradable copolymers, functional macromonomers and biocompatible magnetic nanocomposites. The first part of this work was the synthesis of hyperbranched macromonomer initiated by hydroxyethyl methacrylate (HEMA), hydroxyethyl acrylate (HEA) and polyethylene glycol methacrylate (PEGMA), through the study of the synthesis of polyglycerol (PG) by anionic, anionic coordinated and cationic polymerization of glycidol. Synthesis of poly (ε-caprolactone) macromonomers in the presence of various catalyst systems and initiators was also investigated. This part ends by the synthesis of dendrigrafts derived from the copolymerization of the macromonomers, by free radical polymerization or by controlled radical polymerization. The 2nd part of this work has been devoted to the synthesis of hyperbranched biocompatible copolymers obtained by random copolymerization of glycidol with ε-caprolactone in order to obtain hydrolyzable copolymers. The impact of the structure of the copolymers on their physico-chemical properties was then investigated. The biodegradable behavior of these polymers was then investigated through different enzymatic degradation tests. Finally, this work was focused on the development of biocompatible magnetic nanocomposites by the synthesis of magnetic nanoparticles and the immobilization of linear or hyperbranched polymers on their surface by different chemical grafting methods.
6

Design of telechelic oligo-(caprolactone-co-dioxanone) as photocurable macromonomers for degradable gels / Design av telekelisk oligo(kaprolakton-sam-dioxanon) som fototvärbindande makromonomer för nedbrytbara geler

Nguyen, Tran Tam January 2020 (has links)
Three-dimensional (3D) printing has an important role for fabrication of degradable scaffoldsfor soft tissue regeneration. Among the 3D printing techniques, photopolymerization-based 3Dprinting is one of fastest growing, offering environmental benefits and high precision of 3Dobjects. In this approach, photocurable macromonomers/monomers are cross-linked layer bylayer in the presence of photoinitiators under visible or UV light to fabricate 3D designedobjects. However, a limited biomedical material selection has prevented it from spreading overclinical application. Furthermore, poly(ε-caprolactone), a common degradable polymer usedfor 3D printing, shows not satisfactory physical properties for soft tissue regeneration. Thedearth of materials with proper properties raises the need for novel degradable materials,which should be not only compatible for photopolymerization-based 3D printing but alsosuitable for soft and gel-like scaffold fabrication. Here, the aim was to design photocurable macromonomers consisting of oligo(ε-caprolactoneran-p-dioxanone), oCLDX, with acrylate chain-end groups. A metal-free synthetic strategy wasdeveloped for the bulk ring-opening of ε-caprolactone (CL) and p-dioxanone (DX) at roomtemperature using diphenyl phosphate (DPP) as organocatalyst and multifunctional initiators. The oligomers had low dispersity (<1.2) and targeted molecular weight around 2000 g mol-1.The random sequence and the control over chain growth of oCLDXs were confirmed byreactivity ratios using 1D and 2D NMR analysis. Kinetics study of co-oligomerizationdemonstrated that within DPP-catalysed reaction, DX possessed higher reactivity than CL andthe ring-opening co-oligomerization followed an activated monomer mechanism (AMM). Thetopology of the co-oligomers could also be varied by using different alcohol initiators. The co-oligomers possessed lower degree of crystallinity than homopolymers of DX or CL and,depending on the composition, they were liquid at room temperature. The lower melting pointand gel-like appearance make them good candidates for photopolymerization-based 3Dprinting. The suitability toward photopolymerization was proven for the ethylene glycol-initiatedco-oligomer containing 30 mol% of DX. The cross-linked gels were soft but brittle and showedgood water uptake capacity. / Tredimensionell (3D)-utskrift har en viktig roll vid tillverkning av nedbrytbara matriser förregenerering av mjukvävnad. Bland 3D-utskriftteknikerna är fotopolymerisationsbaserad 3Dutskriften av de snabbast växande, och erbjuder miljöfördelar och hög precision hos 3Dobjekten.För att tillverka 3D-designade objekt med denna teknik är fotohärdandemakromonomerer/ monomerer tvärbundna lager på lager i närvaro av fotoinitiatorer och synligteller UV-ljus. Emellertid har ett begränsat urval av biomedicinska material hindrat tekniken frånatt spridas till kliniska applikationer. Vidare har poly(ε-kaprolakton), en vanlig nedbrytbarpolymer som används för 3D-utskrift, inte tillfredsställande fysikaliska egenskaper förregenerering av mjukvävnad. Bristen på material med rätt egenskaper ökar behovet av nyanedbrytbara material, som inte bara ska vara kompatibla för fotopolymerisationsbaserad 3Dutskriftutan också lämplig för mjuk och gelliknande matristillverkning.Här var syftet att designa fotohärdande makromonomerer bestående av oligo(ε-kaprolaktonsam-p-dioxanon), oCLDX, med akrylatkedjeändgrupper. En metallfri syntetisk strategiutvecklades för bulkringöppning av ε-kaprolakton (CL) och p-dioxanon (DX) vidrumstemperatur genom att använda difenylfosfat (DPP) som organisk katalysator ochmultifunktionella initiatorer. Oligomererna hade den förutbestämda molekylvikten, omkring2000 g mol-1, och en låg dispersitet (<1,2). Den slumpmässiga sekvensen och kontrollen avkedjans tillväxt, till oCLDX, bekräftades genom reaktivitetsförhållanden med hjälp av 1D och2D NMR-analys. Kinetikstudie av samoligomeriseringen visade att med DPP-katalyseradreaktion hade DX högre reaktivitet än CL och att den ringöppnande samoligomeriseringenföljde en aktiverad monomermekanism (AMM). Topologin hos samoligomererna kunde ocksåvarieras genom att använda olika alkoholinitiatorer. Samoligomererna hade lägre grad av kristallinitet än homopolymerer av DX eller CL ochberoende på kompositionen var de flytande vid rumstemperatur. Den lägre smältpunkten ochgelliknande utseendet gör dem till bra kandidater för fotopolymerisationsbaserad 3D-utskrift. Lämpligheten för fotopolymerisation bevisades för den etylenglykolinitierade samoligomerensom innehöll 30 mol% DX. De tvärbundna gelerna var mjuka men spröda och uppvisade godvattenupptagningskapacitet.
7

Synthesis and characterization of polymacromonomers based on polyethers

Mendrek, Aleksandra 24 April 2006 (has links) (PDF)
The synthesis and polymerization of macromonomers containing a polymerizable styrene head group and a tail of ethylene oxide derivatives of different character were investigated. The synthesis of macromonomers was based on living anionic polymerization of oxiranes. Two monomers were used: 1-ethoxyethyl glycidyl ether (glycidol acetal), which after hydrolysis forms hydrophilic glycidol blocks and glycidyl phenyl ether forming hydrophobic blocks. Polymerizable double bonds were introduced by terminating the living chain with p-(chloromethyl)styrene. However, MALDI-TOF-MS end group analysis showed that all synthesized macromonomers were a mixture of the macromonomer and the non-functionalized oligomer. The degree of functionalization varied from 55 to 75 %. The obtained macromonomers showed amphiphilic properties and formed micelles in water. The determined critical micellization (CMC) concentration for poly(glycidol) macromonomer (DP = 50) was ca. 10 g/L, while the poly(glycidol) block macromonomers with hydrophobic spacer showed CMC on the level 0,7 g/L. The conventional free radical and controlled free radical polymerisation (ATRP) were used for preparation of polymacromonomers with different properties. The radical polymerization of the macromonomers was carried out in water using AVA as initiator and in the mixture of water/benzene (10/1 v/v) using AIBN. Core-shell polymers of different character and molar masses with polydispersity indices from 1,4 -3,0 were obtained. The ATRP carried out in water using PEO macroinitiator led to polymacromonomers with polydispersity indices from 1,1 to 1,3 and desiried molecular weight. In all cases the conversion of macromonomer (able to polymerization) was close to 100%. The polymerization product could easily be separated from the unable to reaction residue.
8

Synthesis and characterization of polymacromonomers based on polyethers

Mendrek, Aleksandra 23 May 2006 (has links)
The synthesis and polymerization of macromonomers containing a polymerizable styrene head group and a tail of ethylene oxide derivatives of different character were investigated. The synthesis of macromonomers was based on living anionic polymerization of oxiranes. Two monomers were used: 1-ethoxyethyl glycidyl ether (glycidol acetal), which after hydrolysis forms hydrophilic glycidol blocks and glycidyl phenyl ether forming hydrophobic blocks. Polymerizable double bonds were introduced by terminating the living chain with p-(chloromethyl)styrene. However, MALDI-TOF-MS end group analysis showed that all synthesized macromonomers were a mixture of the macromonomer and the non-functionalized oligomer. The degree of functionalization varied from 55 to 75 %. The obtained macromonomers showed amphiphilic properties and formed micelles in water. The determined critical micellization (CMC) concentration for poly(glycidol) macromonomer (DP = 50) was ca. 10 g/L, while the poly(glycidol) block macromonomers with hydrophobic spacer showed CMC on the level 0,7 g/L. The conventional free radical and controlled free radical polymerisation (ATRP) were used for preparation of polymacromonomers with different properties. The radical polymerization of the macromonomers was carried out in water using AVA as initiator and in the mixture of water/benzene (10/1 v/v) using AIBN. Core-shell polymers of different character and molar masses with polydispersity indices from 1,4 -3,0 were obtained. The ATRP carried out in water using PEO macroinitiator led to polymacromonomers with polydispersity indices from 1,1 to 1,3 and desiried molecular weight. In all cases the conversion of macromonomer (able to polymerization) was close to 100%. The polymerization product could easily be separated from the unable to reaction residue.
9

Cycloalkenyl macromonomers from new multifunctional inimers : a platform for graft, bottle-brush and mikto-arm star copolymers / Macromonomères cycloalcéniques synthétisés à partir d'inimers multifonctionnels originaux : une plateforme pour l'élaboration de copolymères gréffés, en goupillon ou de type "mikto-arm"

Nguyen, Duc Anh 07 January 2016 (has links)
Le sujet de cette thèse concerne l'élaboration de macromonomères, de copolymères greffés et de polymères étoiles de type 'mikto-arm'. De telles architectures macromoléculaires ont été synthétisées par la combinaison de techniques de polymérisation contrôlées/vivantes telles que la polymérisation par ouverture de cycle (par métathèse) (RO(M)P) etde chimie 'click' orthogonales : cycloaddition 1,3-dipolaireazoturealcyne catalysée au cuivre (CuAAC) et thiol-ène.Dans un premier temps, des macromonomères originaux à fonctionnalité polymérisable (oxa)norbornène portant deux chaînes macromoléculaires poly(e-caprolactone) (PCL) et/ou poly(oxyde d'éthylène) (POE) ont été synthétisés par combinaison ROP/CuAAC. Les macromonomères à fonctionnalité (oxa)norbornène avec deux chaînes PCL de masse molaire moyenne en nombre (Mn) compris entre 1400 et 5000 g/mol ont été obtenus par ROP organocatalysée. La synthèse des macromonomères POE44-b-PCLn à fonctionnalité norbornène avec un bloc PCL de longueur variable (1100 g/mol <Mn< 4100 g/mol) a été réalisée par combinaison CuAAC/ROP à partir d'un POE 2000 g/mol commercial. Ces macromonomères présentent des propriétés d'auto-assemblage dans l'eau avec une concentration micellaire critique et un rayon hydrodynamique dont les valeurs augmentent avec la longueur du bloc hydrophobe PCL. Dans un second temps, la réactivité de la fonctionnalité (oxa)norbornène des macromonomères a été étudiée par spectroscopie RMN 1H, chromatographie SEC et spectrométrie MALDI-ToF. Des copolymères greffés à squelettepoly(oxa)norbornène à haute densité de greffons PCL et POE ont été obtenus par ROMP en présence d'amorceurs de Grubbs selon la stratégie "grafting through". La thiol-ène a également été utilisée avec succès pour accéder à des copolymères étoiles de type 'mikto-arm' à base de PCL, POE poly(N-isopropylacrylamide). / The objective of the present thesis was the preparation of complex macromolecules by the combination of controlled/livingpolymerization methods such as ring-opening (metathesis) polymerization (RO(M)P) and highly efficient orthogonal chemistries: copper-catalyzed azide-alkyne coupling (CuAAC) and thiol-ene reactions.In the first part of this work, a series of well-defined structural (co)polymers containing a cycloolefin (norbornene (NB) oroxanorbornene (ONB)) functionality bearing two polymer chains including poly(ε-caprolactone) (PCL) and/or poly(ethylene oxide) (PEO) have been successfully prepared using the combination of ring-opening polymerization (ROP) and CuAAC ‘click’ chemistry. Well-defined (oxa)norbornenyl-functionalized bis-PCL polymers with PCL chain ranging from 1400 to 5000 g/mol were obtained by organocatalyst-mediated ROP. Norbornenyl-functionalized PEO-b-PCL block copolymers with PCL block in the range 1100 to 4100 g/mol were synthesized from commercially available PEO 2000 g/mol by CuAAC followed by ROP of CL. The presence of a hydrophilic PEO chain and a hydrophobic PCL chain in norbornenylfunctionalizedPEO-b-PCL copolymers gives rise to self-assembling properties in water solution. Critical micellar concentrations (CMC)are in the range of 0.08 – 0.006 g/L for copolymers with PCL chain length ranging from 10 to 36 CL units, respectively. Thecorresponding micelles show hydrodynamic diameters in range of 10 – 23 nm with low polydispersities.In the second part of this work, well-defined copolymers were used to prepare bottle-brush and (mikto-arm) star copolymersthrough reactions involving the cycloolefin functionality. On the one hand, high density grafting bottle-brush copolymerspoly(oxa)norbornene-g-bisPCL, polynorbornene-g-PEO/PCL (PNB-g-(PEO/PCL)) and PNB-b-(PNB-g-(PEO/PCL)) were achieved by ROMP according to the ‘grafting through’ strategy using Grubbs’ catalysts. On the other hand, PCL, PEO, PNIPAM-based 3-arms star, 4-arms star copolymers were obtained via radical thiol-ene reactions as demonstrated by 1H NMR, SEC and MALDI-ToF MS analysis.The high reactivity of these copolymers toward ROMP and thiol-ene reactions makes them interesting candidates in order toprepare new well-defined copolymers with controlled structures and properties through highly efficient synthetic strategies.

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