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1

Schlindwein, Walkiria Santos. "Conducting polymers and polymer electrolytes". Thesis, University of Leicester, 1990. http://hdl.handle.net/2381/33889.

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Polymers are mostly used as insulator materials. Since the late sixties, two new classes of polymeric materials possessing either ionic or electronic conductivities have been extensively studied. The work carried out in this thesis concerns of the study of polymer electrolytes based on poly(ethylene oxide) (PEO) complexed with divalent salts (ionic conductors) and polypyrroles (PPy) electrochemically and chemically prepared (electronic conductors). Different techniques were used to study their properties including Differential Scanning Calorimetry (DSC), Variable Temperature Polarising Microscopy (VTPM), Extended X-ray Absorption Fine Structure (EXAFS), a.c. Impedance, Cyclic Voltammetry, and Fourier Transform Infra-Red Spectroscopy (FTIR). Water-cast films of PEOn:ZnX2 (X = C1, Br, I) were prepared at a range of stoichiometries. The effects of either residual presence of water or thermal treatment related to the formation of high melting crystalline materials were investigated. The morphology of the zinc halides films differs from similar films cast from acetonitrile/methanol mixtures. The presence of high melting crystalline material in the water cast samples is influenced mostly by the concentration, type of anion and drying procedure applied to the samples. The high melting crystalline materials in the zinc samples are more affected by the drying regime. In some cases, solvent effects can be removed by using a high temperature (e.g. 180°C) drying regime. The presence of water normally depresses the melting temperature of the crystalline structures. Films of PEOn.:CaBr2 and PEOn:NiBr2 cast from water were also examined. The high melting crystalline materials in the calcium samples are more affected by the presence of water. The nickel samples are highly crystalline and the presence of high melting material does not seem to be influenced by either the presence of solvent or the drying procedure. EXAFS was used as a suitable technique to probe the local structure surrounding the cation. The results of the zinc halide samples gave some indication of the interionic and polymer-cation interactions. It was demonstrated that the halogen provides the most substantial contribution for the total EXAFS spectrum and the oxygen contribution is much less significant, except in the case of PEOn:ZnC12 samples. This could be due to the size of the nearest neighbour atoms and/or to the interaction polymer-cation. The presence of neutral "ion pairing" is suggested for the PEOn:ZnBr2 samples. The EXAFS results for the samples containing NiBr2 indicated a strong interaction between polymer-salt and the local structure was dependent on concentration, unlike the zinc samples. The polymerisation of pyrrole was investigated by using chemical and electrochemical oxidation routes. The structural characterisation of the compounds obtained was limited by their insolubility. The electrochemically prepared samples presented higher conductivity than the ones which were chemically prepared. The EXAFS results at the Fe K-edge of the PPyFeCl4 sample, which was prepared by direct chemical oxidation, suggested that the iron is coordinated to oxygens at a distance 1.97 A, chlorines at 3.08 A and perhaps nitrogens at 3.72 A. The iron local structure of the composite PVA/PPy doped with FeCl3 was different from the PPyFeCl4 sample. The iron in the composite sample was coordinated to oxygens at 1.98 A and chlorines at 2.18 A. Alternatively, the presence of a distorted FeCl4- is considered.
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2

Muangpil, Sairoong. "Functionalised polymers and nanoparticle/polymer blends". Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.654111.

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The incorporation of nanoparticles into polydimethylsiloxane polymers either in the form of physical blending or chemical crosslinking has long been studied as it can improve the properties of composite materials. Interactions between the host polymer and the filler particle, filler concentration and conformation of each component are the key factors that influence these properties. Understanding the effect of these factors is of fundamental importance in all practical applications of composite materials. This thesis describes the study of a range of PDMS composites by using a variety of experimental techniques. The main techniques used were spin-spin (T2) relaxation and diffusion NMR spectroscopy, rheology and small-angle neutron scattering (SANS). The molecular mobility of a series of PDMS melts has been studied for both unentangled and entangled molecular weight regimes separated by the critical entanglement molecular weight (Mc) of the polymer. The experimental results revealed the effect of molecular weight and polydispersity of the polymers on their segmental mobility. The dramatic decrease of chain mobility observed at molecular weight above Mc was attributed to the effect of chain entanglements. The effect of nano-sized trimethylsilylated polysilicate resin (R2) on the chain mobility of PDMS in the form of physically blended was also examined. Two different concentrations (17 and 30 vol%) of R2 were incorporated into a wide range molecular weight of PDMS melts. Below Mc, the R2 particle was found to reinforce the PDMS at all particle loadings, whereas a plasticisation effect was observed for high molecular weight PDMS above Mc. This was attributed to a reduction of the degree of the entanglements when polymer chains adsorbed on particles. Chemically bonded composites of PDMS and polyhedral oligomeric silsesquioxane (POSS) were successfully synthesised via hydrosilylation. The length of the PDMS central block was found to affect both the size and the molecular mobility of the triblock polymers. The weight fraction of POSS and substituted groups on POSS were also seen to affect the molecular mobility. Finally, a series ofrandom crosslink polymer films ofPDMS and phenylsilsesquioxane (TPh) was studied by AFM, TEM, SAXS and SANS techniques to investigate the factors influencing the optical clarity of the samples. The degree of swelling and the segmental mobility of the sample films swollen in good and poor solvents were also studied.
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3

Chester, Shawn Alexander. "Mechanics of amorphous polymers and polymer gels". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68898.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 345-356).
Many applications of amorphous polymers require a thermo-mechanically coupled large-deformation elasto-viscoplasticity theory which models the strain rate and temperature dependent response of amorphous polymeric materials in a temperature range which spans the glass transition temperature of the material. We have formulated such a theory, and also numerically implemented our theory in a finite element program. The material parameters in the theory have been calibrated for poly(methyl methacrylate), polycarbonate, and Zeonex - a cyclo-olefin polymer. The predictive capabilities of the constitutive theory and its numerical implementation have been validated by comparing the results from a suite of validation experiments against corresponding results from numerical simulations. Amorphous chemically-crosslinked polymers form a relatively new class of thermallyactuated shape-memory polymers. Several biomedical applications for thermally-actuated shape-memory polymers have been proposed/demonstrated in the recent literature. However, actual use of such polymers and devices made from these materials is still quite limited. For the variety of proposed applications to be realized with some confidence in their performance, it is important to develop a constitutive theory for the thermo-mechanical response of these materials and a numerical simulation-based design capability which, when supported with experimental data, will allow for the prediction of the response of devices made from these materials under service conditions. We have developed such a theory and a numerical simulation capability, and demonstrated its utility for modeling the thermo-mechanical response of the shape-memory polymer tBA-PEGDMA. An elastomeric gel is a cross-linked polymer network swollen with a solvent, and certain thermally-responsive gels can undergo large reversible volume changes as they are cycled about a critical temperature. We have developed a thermodynamically-consistent continuum-level theory to describe the coupled mechanical-deformation, fluid permeation, and heat transfer of such gels. We have numerically implemented our theory in a finite element program by writing thermo-chemo-mechanically coupled elements. We show that our theory is capable of simulating swelling, squeezing of fluid by applied mechanical forces, and thermally-responsive swelling/de-swelling of such materials.
by Shawn Alexander Chester.
Ph.D.
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4

Mohagheghian, Iman. "Impact response of polymers and polymer nanocomposites". Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648854.

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5

Sun, Shuangyi. "Alkoxyphenacyl Polymers: A Novel Photodegradable Polymer Platform". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1424234383.

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6

Michal, Brian. "Multi-Functional Stimuli-Responsive Polymers". Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1459440396.

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7

Smartt, William Mark. "Formation of microporous polymer via thermally-induced phase transformations in polymer solutions". Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/32853.

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8

Amalou, Zhor. "Contribution à l'étude de la structure semi-cristalline des polymères à chaînes semi-rigides". Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210832.

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Les polymères semi-cristallins à chaînes semi-rigides, bien qu’abondamment utilisés dans la vie quotidienne, représentent des systèmes complexes qui ne sont pas encore parfaitement compris. Parmi les nombreux domaines de recherche sur cette famille de polymères, l’étude de la morphologie semi-cristalline et des processus de cristallisation et de fusion de ceux-ci restent des sujets très importants. L’investigation de la morphologie semi-cristalline est rendue difficile car elle présente une structure hiérarchique composée de plusieurs niveaux d’organisation, dont le plus petit est observable à une échelle très réduite de quelques nanomètres. De plus, les aspects liés à la cinétique des processus de cristallisation et de fusion n’ont pas toujours permis de bien les mettre en évidences, les rendant ainsi par très bien compris. Cependant, les nouvelles avancées technologiques dans le domaine de la physique expérimentales ont beaucoup profité à la science des polymères.

Dans ce travail, une contribution originale est apportée à cette étude, et cela en combinant diverses techniques expérimentales permettant des mesures calorifiques et structurales en températures et temps réels. L’intérêt c’est porté sur les polymères linéaires aromatiques tels que le polyéthylènes teréphthalate, PET, et le polytriméthylène téréphthalate, PTT, caractérisés par une température de transition vitreuse supérieure à l’ambiante ( Tg > 50°) et une température de fusion élevée (Tm>220°C), offrant ainsi une assez large gamme de température de cristallisation (Tm-Tg). L’étude de la structure semi-cristalline du PET à l’échelle du nanomètre et de la relaxation des phases amorphes présentes dans sa structure est facilitée par l’utilisation d’un diluant amorphe tel que le polyétherimide (PEI), qui forme un mélange miscible avec le PET.

L’utilisation de microscopie de force atomique AFM à haute température a permis d’observer la cristallisation isotherme de PET en temps réel et de décrire ainsi la cristallisation secondaire comme un processus d'épaississement des piles lamellaires. De plus, l’analyse de la structure semi-cristalline du PET et du PTT, dans l’espace direct, sont en faveur d’un modèle structural homogène, où l’épaisseur lamellaire moyenne est légèrement inférieure à l’épaisseur moyenne des régions amorphes interlamellaires. Ces résultats ont permis, d’une part, d’apporter une meilleure interprétation aux données obtenues par diffusion des rayons X aux petits angles (SAXS), et d’autre part, d’ interpréter le comportement de fusion multiple caractéristique des polymères semi-cristallin à chaînes semi-rigides par le seul processus de fusion-recristallisation. Dans l’étude investiguée sur les mélanges PET/PEI et sur le PTT pur, on montre que la cinétique d’un tel processus est particulièrement rapide comparée à la cristallisation. De plus, les observations par AFM et par microscopie optique de même que les mesures SAXS en temps réel ont montré la simultanéité et la compétition existant entre la fusion des cristaux et leur réorganisation durant la chauffe. Par ailleurs, la relaxation des régions amorphes interlamellaires, souvent considérées comme rigides, a pu être mise en évidence par les mesures AFM et SAXS réalisées à haute température sur des échantillons de PET/PEI semi-cristallins.


Doctorat en sciences, Spécialisation physique
info:eu-repo/semantics/nonPublished

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9

Cooke, Richard Hunter III. "THE ENHANCEMENT OF PEROXIDE-CURED FLUOROELASTOMER RUBBER TO METAL BONDING". Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1377022145.

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10

Yang, Lianyun. "Novel Ferroelectric Behavior in Poly(vinylidene fluoride-co-trifluoroethylene)-Based Random Copolymers". Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1431686125.

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11

He, Yinghui. "Novel N-type Π-conjugated Polymers for all-polymer solar cells". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0651/document.

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Les cellules solaires organiques (OSC) apparaissent comme une technologie prometteuse pour les énergies renouvelables en raison de leur poids léger, leur grande flexibilité et leur processus de fabrication peu coûteux. Jusqu'à présent, la plupart des OPV ont utilisé des dérivés de Fullerene, tels que PCBM ou PC71BM, en tant qu'accepteur d'électrons dans la couche active, qui s'est avéré être un goulet d'étranglement pour cette technologie. Par conséquent, le développement d'accepteurs non-fullerene est devenu la nouvelle force motrice de ce domaine. Les cellules solaires tout-polymères (tous-PSC) qui ont les avantages de la robustesse, de la stabilité et de l'accessibilité ont déjà atteint PCE jusqu'à 9%. Ainsi, le développement de nouveaux matériaux accepteurs est impératif pour améliorer les performances de tous les PSC
Organic solar cells (OSCs) appear as a promising technology for renewable energy owing to their light weight, great flexibility and low-cost fabrication process. So far most of the OPV shave been using fullerene derivatives, such as PCBM or PC71BM, as the electron acceptor in the active layer, which have been proven to a bottleneck for this technology. Therefore,developing non-fullerene acceptors has become the new driving force for this field. All-polymer solar cells (all-PSCs) that have the advantages of robustness, stability and tunability have already achieved PCE up to 9%. Thus, developing novel acceptor materials is imperative for improving the performance of all-PSCs
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12

Liu, Gengxin. "Nonlinear Rheology of Long-Chain Branched Polymers". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1436977058.

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13

Prabhakar, Roopa Lakshmi. "Characterisation of Novel Polymers and polymeric Systems". Thesis, University College London (University of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498710.

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14

Gurun, Bilge. "Deformation studies of polymers and polymer/clay nanocomposites". Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37118.

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Polymer clay nanocomposites have been a popular area of materials research since they were first introduced in the 1990s. The inclusion of clays into many different host polymers has been shown to improve the properties of matrix polymers in a number of ways including increased mechanical strength, thermal stability and improved barrier properties while keeping the composite light weight and transparent. Although there is a great deal of published work on the preparation and property measurements of polymer clay nanocomposites, there is no model to design a nanocomposite with a given set of properties for a specific end-use. While it is important to know the structure property relationships of materials, the understanding of how nanocomposites reach their final forms and properties is equally important. A thorough understanding of processing effects on the final structure of polymer clay nanocomposites is still missing. With this perspective, this thesis addresses building structure-processing relationships of polymer clay nanocomposites by analyzing multiaxial deformation behavior using in-situ x-ray scattering techniques. This thesis can be divided into two distinct parts. The first part concerns the design of the in-situ multiaxial deformation device (IMDD) used to create the deformation conditions that polymers go through during processing such as blow molding and thermoforming. The device was designed to overcome several concerns with in situ measurement by maintaining constant sample to detector distance, minimizing the material between the incident beam and the detectors, as well as exposing the same point on the sample throughout deformation. A new design to create biaxial deformation, termed in-situ biaxial deformation device (IBDD), is also introduced in this part of the thesis.. In addition, a new heating unit, attached to IBDD, is designed for higher temperature studies, up to 150°C, to imitate industrial processing conditions more closely. The second part of the thesis addresses the effect of strain, strain rate, and temperature as well as the amount of clay on the polymer morphology evolution during multiaxial deformation.. Two different polymer/clay systems were studied: poly(ethylene)/clay and poly(propylene)/clay. It was observed that the morphological evolution of polyethylene and polypropylene is affected by the existence of clay platelets as well as the deformation temperature and the strain rate. Martensitic transformation of orthorhombic polyethylene crystals into monoclinic crystal form was observed under strain but is hindered in the presence of clay nanoplatelets. The morphology evolution of poly(propylene) crystal structure during multiaxial deformation was more subtle where the most stable α-crystalline form went through strain induced melting. This was more noticeable in the nanocomposites with clays up to 5 wt%. It was also noted that the thickness of the interlamellar amorphous region increased with increasing strain at room temperature due to the elongation of the amorphous chains. The increase in the amorphous layer thickness is slightly higher for the poly(ethylene)/clay nanocomposites compared to neat poly(ethylene) while the increase in the lamellar long spacing is slightly higher for the neat poly(propylene) compared to poly(propylene)/clay nanocomposites. The rate of change in the characteristic repeat distance in both poly(ethylene) and poly(propylene) systems is higher at faster strain rates, at room temperature, where it remained constant during higher temperature deformations. Time dependent recovery after deformation studies have shown that poly(ethylene)/clay system reverts back to its initial configuration. The recovery in the amorphous chains was however observed to take longer in the clay added poly(ethylene)s. Crystalline relaxation was observed to happen almost instantly in the poly(ethylene)/clay system. On the other hand, amorphous chains in the poly(propylene)/clay system did not revert back to the initial configuration in the period of time that the recovery observations were performed while the crystalline configuration recovered back almost fully in the given time.
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15

Mahaffy, Rachel Elaine. "The quantitative characterization of the viscoelastic properties of cells and polymer gels /". Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004328.

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16

Harding, Gareth. "The fractionation and characterisation of propylene-ethylene random copolymers". Thesis, Link to online version, 2005. http://hdl.handle.net/10019/1040.

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17

Kumagai, Masashi. "The synthesis and characterization of novel nitrogen-containing ladder polymers and their model compounds as possible precursors to organic ferromagnetic polymers". Case Western Reserve University School of Graduate Studies / OhioLINK, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=case1058965935.

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18

Kumpfer, Justin Richard. "Utilizing Metallosupramolecular Polymers as Smart Materials". Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1333553702.

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19

Chernykh, Andrey. "Main Chain Type Benzoxazine Polymers for High Performance Applications". Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1232733414.

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20

Joyce, Steven John. "The topological trapping of cyclic polymers into polymer networks". Thesis, University of York, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306470.

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21

Jezzard, Peter. "Nuclear magnetic resonance imaging of polymers and polymer-composites". Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277832.

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22

Sen, Mustafa Yasin. "Green Polymer Chemistry: Functionalization of Polymers Using Enzymatic Catalysis". University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1258422775.

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23

Callies, Xavier. "Rheology and Adhesion of Supramolecular Center-functionalized Polymers". Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066663.

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Les adhésifs sensibles à la pression (PSAs) sont constitués de matériaux polymères mous qui collent presque instantanément sur presque tout type de surface. Les propriétés adhésives de ces matériaux sont principalement contrôlées par leurs propriétés rhéologiques et ainsi, par la structure moléculaire des polymères utilisés dans leur formulation. La nature des monomères, la distribution des masses molaires et le degré de réticulation sont des exemples de paramètres habituellement définis par les ingénieurs pour l’optimisation des adhésifs commerciaux. La singularité de notre projet est d’étudier les propriétés adhésives de matériaux polymères modèles fonctionnalisés par des groupements urée.Ces groupements fortement interactifs par liaison hydrogène renforcent les propriétés élastiques et dissipatives de la matrice polymère constituée de chaînes non enchevêtrées, tout en gardant une très faible viscosité dans les solvants non polaires. Inspiré de l’étude récente sur le PIBUT (Courtois et al, Adv .Func. Mater. 2010), nos systèmes modèle sont constitués de chaînes linéaires polybutylacrylate fonctionnalisées en leur milieu. La méthode de synthèse utilisée dans notre projet permet un très bon contrôle de la longueur des chaînes, tout en permettant d’utiliser une grande diversité de groupements interactifs. La caractérisation systématique de nos matériaux nous a permis d’identifier les paramètres structuraux qui gouvernent la rhéologie et l’adhésion. Des structures supramoléculaires plus complexes ont aussi été explorées dans notre projet et montrent clairement le fort potentiel de la chimie supramoléculaire pour le domaine de l’adhésion
Pressure Sensitive Adhesives (PSA) are soft polymer materials which stick on almost any surface due to their particular rheological properties. Engineers adjust polymers molecular structure to optimize adhesion properties for each application. The nature of the monomers, molecular weight distribution and degree of crosslinking are classical tunable parameters for acrylic adhesives. The specificity of our project is to investigate the adhesive properties of model polymers functionalized by urea groups. The presence of strong hydrogen bonds inside the polymeric matrix allows to dramatically increase the viscosity and dynamic modulus of short polymer chains (M<20kg/mol) reducing the need for crosslinking while reducing dramatically the viscosity when dissolved in polar solvents. Inspired by the recent study on PIBUT (Courtois et al, Adv .Func. Mater. 2010), our model systems are linear center-functionalized polybutylacrylate chains synthesized with a highly controlled but versatile synthesis method. In our work, the extensive characterization of these materials allowed us to identify the key structural parameters governing their rheology and their adhesive properties. More complex structures were also investigated and showed clearly the potential of the supramolecular chemistry for the science of adhesion
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Lee, William K. "Solid-gel interactions in geopolymers". Connect to thesis, 2002. http://repository.unimelb.edu.au/10187/1071.

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This is partly because the requirements for such an ultimate material change with people’s perception about its properties as well as its environmental impact. Thus, the once-believed ultimate Portland cement binder is now becoming unacceptable for a number of reasons including poor durability as well as severe environmental impact during production. Thus, an improved mineral binder is required by modern society to serve the same purposes as the existing Portland cement binder, as well as to reduce the current environmental impact caused by Portland cement production.
Geopolymerisation is such a ‘green’ technology capable of turning both natural ‘virginal’ aluminosilicates and industrial aluminosilicate wastes, such as fly ash and blast furnace slag, into mechanically strong and chemically durable construction materials. However, the source materials for geopolymer synthesis are less reactive than Portland cement clinkers and the chemical compositions of these source materials can vary significantly. Consequently, product quality control is a major engineering challenge for the commercialisation of geopolymers.
This thesis is therefore devoted to the mechanistic understanding of the interfacial chemical interactions between a number of natural and industrial aluminosilicates and the various activating solutions, which govern the reactivity of the aluminosilicate source materials. The effects of activating solution alkalinity, soluble silicate dosage and anionic contamination on the reactivity of the aluminosilicate source materials to produce geopolymeric binders, as well as their bonding properties to natural siliceous aggregates for concrete making, are examined. In particular, a new set of novel ‘realistic’ reaction models has been developed for such purposes. These reaction models have been further utilised to develop a novel analytical procedure, which is capable of studying geopolymerisation on ‘real’ geopolymers in situ and in real time. This novel procedure is invaluable for the total understanding of geopolymerisation, which is in turn vital for effective geopolymer mix designs.
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Markotsis, Martin G. School of Chemical Engineering &amp Industrial Chemistry UNSW. "Morphological studies of sbs based interpenetrating polymer networks". Awarded by:University of New South Wales. School of Chemical Engineering and Industrial Chemistry, 2005. http://handle.unsw.edu.au/1959.4/32833.

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Interpenetrating polymer networks (IPNs) of polystyrene-polybutadiene-polystyrene (SBS) block copolymers and polystyrene (PS) were prepared using sequential network formation with the polybutadiene (PB) of the SBS crosslinked thermally and the styrene network formed thermally or by ??-radiation. The use of ??-radiation to cure the added PS network at room temperature successfully avoided thermal degradation of the butadiene segments within the SBS which had been observed in earlier studies. Both linear SBS and radial SB4 IPNs were studied to compare the influence of linear or branched block copolymers on the IPN morphology. The molecular morphology was examined using a suite of techniques including thermal analysis (DSC and DMA), transmission electron microscopy (TEM), atomic force microscopy (AFM) and smallangle X-ray and neutron scattering (SAXS and SANS). The primary SBS/SB4 network morphology was found to dominate the IPN morphology with the secondary styrene network limited to selectively swelling the PS domains. The linear SBS IPNs displayed a more ordered morphology than the radial SB4 IPNs, and this morphology was investigated in pseudo three-dimensions by sectioning samples in two perpendicular directions. The morphology was found to be consistent with thermally formed systems prepared in previous studies, and contained styrenic domains of 20-50 nm within a continuous butadiene matrix. The weight of evidence suggested that the lamella structure dominated the linear SBS IPNs and a cylindrical structure for the radial SB4 IPNs. Maximum values of tensile strength and elongation at break (20 MPa and 140% respectively) were observed in samples with a styrene cure ??-radiation dose of 200 kGy. The SANS analysis of these polymer systems was expanded to investigate the thermal formation of the added PS network in real time. Time-resolved SANS allowed the development of nanostructures in the bulk samples to be measured, and compared to previous time-independent TEM studies on thin sections. The formation of the styrene network was most noticeably observed in a linear SBS IPN system, in which an increase in long-range order was observed and attributed to movement of styrene monomer into the styrenic domains and sharpening of the phase boundaries between the PS and the PB regions.
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Qu, Haoran. "SOLUTION SELF-ASSEMBLY OF HEXAETHYLENE GLYCOL-FUNCTIONALIZED POLYHEDRAL OLIGOMERIC SILSESQUIOXANE (GPOSS) TETHERED WITH POLYSTYRENE CHAIN". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1486638275556455.

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27

Zartman, Gregory D. "The Effects of Melt Stretching on the Mechanical Behavior of Polymer Glasses". University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1342409357.

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28

Li, Mingxuan. "Self-Assemble of Novel Discotic Nano-Molecules Based on Polyhedraloligomericsilsesquioxanes". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399242960.

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29

Wang, Yi. "The Synthesis and Characterization of Amphiphilic Poly(Ethylene Oxide)-Block-Poly(Octadecyl Acrylate) Block Copolymers". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399491109.

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30

Zhu, Sunsheng. "Novel Approach to Polyhedral Oligmeric Silsesquioxane-Based Giant Surfactants Basd on Thiol-Michael Addition "Click" Reaction". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399555570.

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31

Chu, Yang. "Enhancement of Photocatalytic Activity by Site Poisoning Platinum Doped Titanium Dioxide". University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1417454495.

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32

Chen, Junyi. "Oligo(ß-Alanine)-Grafted Butyl Rubber (IIR) with Mixed O(ligo(ß-Alanine) Lengths". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1427827046.

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33

Liu, Jianning. "Stress Relaxation Behavior of Polymer Glasses in Both Extension and Compression". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1427995606.

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34

Shi, Feimo. "A THERMO- AND LIGHT- SENSITIVE STAR-LIKE COPOLYMER: DESIGN, SYNTHESIS, AND POTENTIAL APPLICATION FOR DRUG DELIVERY SYSTEM". Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1428072959.

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35

Zhong, Weijie. "The Effect of Hydrophilic Monomer in Core-shell Latex". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1436453067.

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36

HE, ZHOUYING. "ORGANIC/INORGANIC HYBRID COATINGS FOR ANTICORROSION". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1437870016.

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37

Pangilinan, Katrina Dayoan. "Layer-by-Layer and Photochemical Grafting of ATRP Initiators for Thermoresponsive Surfaces". Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1448375686.

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38

Sun, Jian. "Molecular Janus Particles Based On Functionalized [60]Fullerenes: Precise Synthesis And Self-Assembly Behaviors In Solution". University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460373051.

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39

Stilke, Morgan A. "Diffusive and Deformation Behavior of Physically Crosslinked Hydrogels". University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460384954.

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40

Ji, Xiang Ji. "THE INFLUENCE OF ASSEMBLY PH AND CLAY INCLUSION ON THE ACTUATION OF POLYELECTROLYTE MULTILAYERS". University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1468526322.

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41

Zhang, Zeyang. "INTERFACIAL FREE RADICAL POLYMERIZATION OF MALEIC AND 1,4-CYCLOHEXANEDIMETHYANOL DIVINYL ETHER". University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1468681937.

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42

Chamsaz, Elaheh Anna. "Design and Applications of Biodegradable and Photoresponsive Polymers based on Alkoxyphenacyl and Coumarin Moieties". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1490015846298687.

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43

Yang, Xing. "Synthesis and Self-assembly of Giant Shape Amphiphiles Based on Rod-like Polymers and Precisely Functionalized Fullerenes". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1491576298738033.

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44

CHEN, RUISI. "A Viscosity Modifier: Oligo(¿-Alanine) End-Functionalized Polypropylene". University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1491609493145333.

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45

Zhang, Zhongbo. "Understanding Ferroelectricity in Nylon Homopolymers, Copolymers, and Terpolymers". Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1521638812926921.

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46

Li, Zhuoran. "Synthesis and Characterization of Functionalized Polyurethanes with Hydrophilic Moieties". University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1522851826350018.

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47

Xie, Shaoxiong. "COMPARATIVE STUDY ON TIP/TIA/ZRP/TEOS MODIFIED EPOXIDES RESIN: ANTI-CORROSION PERFORMANCE". University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1534159109126582.

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48

Yuan, Yichun. "Optimized Synthesis of SO2-PIM for Potential Applications in Flexible Electronic Devices". Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1553868388453831.

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49

Zhao, Zhichen. "Understanding melt-deformation effect on mechanical behavior of polymer glasses". University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555001830982788.

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50

Liang, Honghe. "Synthesis and Characterization of A New Catechol Derived Coupling Agent". University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1555671275779722.

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