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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

Quantitative evaluation and interpretation of polymer-polymer interactions

Zhu, Shixiong 27 July 2011 (has links)
Not available / text
2

Deciphering spatially heterogeneous polymer dynamics using single molecule microscopy

Bartko, Andrew P. 05 1900 (has links)
No description available.
3

Structure and mechanical properties of oriented polyoxymethylene.

January 1982 (has links)
Huang Ching-wei. / Bibliography: leaves 111-112 / Thesis (M.Phil.)--Chinese University of Hong Kong, 1982
4

Laser light scattering studies of polymer chain dynamics.

January 1995 (has links)
by Chan Kam Kwong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references. / Abstract --- p.i / Acknowledgment --- p.iii / Contents --- p.iv / Abbreviation --- p.vi / List of Figures --- p.ix / List of Tables --- p.xii / Introduction --- p.xiii / Chapter 1. --- Basic Theories / Chapter 1.1 --- Static light scattering --- p.1 / Chapter 1.2 --- Dynamic light scattering --- p.11 / Chapter 1.3 --- LLS instrumentation --- p.19 / References --- p.20 / Chapter 2. --- "Light-Scattering Evidence of a ""Critical"" concentration for Polymer Coil Shrinking in Dilute Solution" / Chapter 2.1 --- Introduction --- p.23 / Chapter 2.2 --- Theoretical Background --- p.25 / Chapter 2.3 --- Experimental --- p.30 / Chapter 2.4 --- Results and Discussion --- p.31 / Chapter 2.5 --- Conclusions --- p.37 / Reference --- p.38 / Chapter 3. --- Experimental Study of the Spectral Distribution of the Light Scattered from Flexible Macromolecules in Very Dilute Solution / Chapter 3.1 --- Introduction --- p.40 / Chapter 3.2 --- Theoretical Background --- p.42 / Chapter 3.3 --- Experimental --- p.44 / Chapter 3.4 --- Results and Discussion --- p.45 / Chapter 3.5 --- Conclusions --- p.59 / References --- p.59 / Chapter 4. --- Characterization of Pauci-Chain Polystyrene Microlatices Prepared by Chemical Initiator / Chapter 4.1 --- Introduction --- p.61 / Chapter 4.2 --- Experimental --- p.63 / Chapter 4.3 --- Results and Discussion --- p.64 / Chapter 4.4 --- Conclusions --- p.81 / References --- p.82
5

Laser light-scattering characterization of special polymers.

January 1996 (has links)
by Mohammad Siddiq. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 167-176). / Abstract --- p.I / Acknowledgment --- p.II / Contents --- p.III / Abbreviations --- p.iv / List of Figures --- p.vi / List of Tables --- p.xiv / Chapter 1 --- Introduction --- p.1 / Chapter 2. --- Theoretical background / Chapter 2.1 --- Static light scattering --- p.5 / Chapter 2.2 --- Dynamic light scattering --- p.17 / Chapter 2.3 --- Chain flexibility --- p.25 / Chapter 3. --- Instrumentations / Chapter 3.1 --- Laser Light Scattering (LLS) measurements --- p.34 / Chapter 3.2 --- Refractive index increment --- p.34 / Chapter 3.3 --- Size Exclusive Chromatography (SEC) --- p.37 / Chapter 4. --- LLS Study of Novel Thermoplastics --- p.38 / Chapter 5. --- LLS Study ofPoly(sulfoalkyl Methacrylate)s --- p.96 / Chapter 6. --- LLS Study of soluble Polyimides --- p.112 / Chapter 7. --- LLS and SEC Study of Hydroxy ethyl Cellulose acetates --- p.135 / Chapter 8. --- LLS Study of hydrolyzed and unhydrolyzed polyacrylamides --- p.153 / Chapter 9. --- References --- p.167 / Chapter 10. --- List of Publications --- p.177
6

Light scattering studies on several fundamental problems in polymer solution. / CUHK electronic theses & dissertations collection

January 1996 (has links)
by Yubao Zhang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (p. 138-146). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
7

Chemistry and characterization of cycloaddition polyimides

Ngo, Thomas T. 08 1900 (has links)
No description available.
8

Polymer degradation in sliding elastohydrodynamic lubrication

Walker, David Leroy 12 1900 (has links)
No description available.
9

Analysis and remediation of phthalate ester plasticizers and their degradation products in the aquatic environment

Mtibe, Asanda 25 February 2014 (has links)
M.Sc. (Chemistry) / Please refer to full text to view abstract
10

Advanced analytical methods for the analysis of complex polymers prepared by RAFT and RITP

Wright, Trevor Gavin 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Synthetic polymers are complex compounds that have multiple distributions with regard to molar mass, chemical composition, functionality and molecular architecture. Therefore, the molecular complexity of these compounds can only be analysed using a combination of analytical techniques. Well-defined complex polymers can be prepared by different types of living radical polymerisation, including reversible addition–fragmentation chain transfer polymerisation (RAFT) and reverse iodine transfer polymerisation (RITP). Using these techniques, several different homopolymers and copolymers have been prepared. However, there is still space for some more extended research. Many different types of multifunctional RAFT agents have been reported in literature. A tetrafunctional RAFT agent was prepared in our laboratory and used for the first time in the polymerisation of styrene. The polymerisation reaction was followed using in situ 1H nuclear magnetic resonance (NMR) and the molar masses of the resultant polymers were determined using size exclusion chromatography (SEC). The molar masses of the star-shaped polystyrenes (PS) were found to be less than the theoretical molar masses. This was due to the fact that SEC was calibrated with linear PS standards, while the samples under investigation are branched. Linear and branched polymers have different hydrodynamic volumes at similar molar masses. In order to prove that the star-shaped polymers were in fact four-armed, the samples were cleaved by aminolysis to yield the linear PS arms. The molar masses of the arms were in agreement with the theoretical arm molar masses based in the fourarmed structure. RITP is a relatively new living radical polymerisation technique. Various monomers have been prepared using RITP, including acrylates, methacrylates and styrene. The polymers formed using this technique have been characterised by techniques such as SEC, NMR and mass spectrometry (MS). However, very little advanced characterisation work has been done on polymers synthesised via RITP. Polystyrene-block-poly(n-butyl acrylate) (PS-b-PBA) block copolymers were prepared via RITP and the microstructure analysed by in situ NMR and other advanced analytical techniques. The chromatograms from gradient HPLC of the PS-b-PBA block copolymers showed a separation based on chemical composition. The preparation of deuterated polymers via RITP has not been reported in literature. Hydrogenous-polystyrene-block-deuterated-polystyrene (hPS-b-dPS) was synthesised via RITP and analysed using liquid chromatography at critical conditions. An isotopic separation was achieved when critical conditions were established for hydrogenous PS (h-PS). A separation of the block copolymer from the first block was also achieved under chromatographic conditions where the block copolymer eluted in SEC mode while the first block eluted in LAC mode. The separation according to the block structure was confirmed by two-dimensional liquid chromatography. / AFRIKAANSE OPSOMMING: Sintetiese polimere is komplekse verbindings wat meervoudige verspreidings ten opsigte van molêre massa, chemiese samestelling, funksionaliteit en molekulêre argitektuur. Daarom kan die molekulêre kompleksiteit van hierdie verbindings net ontleed word met behulp van 'n kombinasie van analitiese tegnieke. Goed-gedefinieerde komplekse polimere kan voorberei word deur verskillende soorte lewende radikaal polimerisasie, insluitend omkeerbare addisie-fragmentasie kettingoordrag polimerisasie (OAFO) en omgekeerde jodium oordrag polimerisasie (OJOP). Met behulp van hierdie tegnieke, was verskeie homopolimere en kopolimeer opgestel. Maar daar is nog plek vir nog uitgebreide navorsing. Baie verskillende tipes multifunksionele OAFO agente is aangemeld in die letterkunde. Ons het 'n nuwe vier-armige OAFO agent in ons laboratorium voorberei en dit was vir die eerste keer in die polimerisasie van stireen gebruik. Die polimerisasie reaksie is gevolg met behulp van in situ 1H kernmagnetieseresonans (KMR) en die molêre massas van die gevolglike polimere was bepaal deur grootteuitsluitings chromatografie (SEC). Die molêre massas van die ster-polistireen (PS) is bevind as minder as teoretiese molêre massas. Dit is omdat SEC instrumente gekalibreer word met lineêre PS standaarde, terwyl die monsters wat tans ondersoek word vertakte polimere is. Lineêre en vertakte polimere het verskillende hidrodinamiese volumes by soortgelyke molêre massas. Ten einde te bewys dat die ster polimere in werklikheid vier-armig is, is die monsters gesny deur ‘n aminolisasiereaksie om die lineêre PS arms te lewer. Die molêre massas van die arms was ooreenkomstig met die teoretiese arm molêre massas gebaseer op die vier-armige struktuur. OJOP is 'n relatiewe nuuts lewende radikaal polimerisasie tegniek. Verskeie monomere is opgestel deur OJOP, insluitend akrilate, metakrilate en stireen. Die polimere wat gevorm is deur middel van die tegniek is al gekenmerk deur tegnieke soos SEC, KMR en massaspektrometrie (MS). Tog is daar baie min gevorderde karakterisering werk gedoen oor polimere gesintetiseer deur middel van OJOP. Polistireen-blok-poli(n-butylacrylaat) (PS-b-PBA) blokkopolimere was voorberei deur middel van OJOP en die mikrostruktuur ontleed met behulp van gevorderde analitiese tegnieke. Die chromatogramme van gradiënt HPLC van die PS-b-PBA blokkopolimere het 'n skeiding ondergaan gebaseer op die chemiese samestelling. Die voorbereiding van gedeutereerde polimere deur middel van OJOP word nie in die letterkunde gevind nie. Gehidrogeneerde-polistireen-blok-gedeutereerde-polistireen (hPS-b-dPS) is gesintetiseer deur middel van OJOP en ontleed met behulp van vloeistofchromatografie onder kritiese kondisies. 'n Isotopiese skeiding was bereik wanneer kritiese kondisies gestig is vir gehidrogeneerde PS (h-PS).'n Skeiding van die blok kopolimeer van die eerste blok was ook bereik onder chromatografiese omstandighede waar die blok kopolimeer elueer in SEC terwyl die eerste blok elueer in LAC. Die skeiding volgens die blok struktuur was bevestig deur twee-dimensionele vloeistofchromatografie.

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