Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 23 for “"hyperbranched polymers"”.
-
Molecular Modeling Studies of Dendrimers and Hyperbranched Polymers
… and rheological dynamics of dendrimers and hyperbranched polymers is investigated. Non-Equilibrium Brownian Dynamics (NEBD) simulations are utilized to investigate the single-molecule behavior in the dilute solution and the Tube Model is utilized to investigate the dynamics in the entangled …
-
Hyperbranched polymers and Haag type dendrimers for the molecular imprinting of polymers
… imprinted polymer was synthesized using both hyperbranched polyglycerol and Haag type polyether dendrons with estradiol as a core. The attachment of the polyether dendron created a dendrimer that had 64 allyl groups available for crosslinking. Completion of the crosslinking of the dendrimer …
-
Polymeric nanocarriers with dendritic core-shell architectures
Hyperbranched polymers, polyglycerol and polyethylenimine, were functionalised in order to tailor systems that can be used in medical applications. The systems described in this thesis can be used for pH controlled release of drug molecules and were also investigated towards their gene transfection …
-
Self-Condensing Ring-Opening Metathesis Polymerization
… materials with different topologies, including hyperbranched polymers—polymers with high degrees of branching and many end groups. However, hyperbranched polymer synthesis via ROMP is challenging due to multifunctional-monomer or multi-polymerization requirements. To simplify the synthesis of …
-
Using Branching and Endgroups to Control the Physical Properties of Macromolecules: Systematic Studies of Etherimide Polymers
… physical properties, end-group modified hyperbranched polyetherimides were prepared by a one-pot, two-step reaction sequence. General synthetic techniques were developed to prepare both mono-functional terminating segments and the corresponding modified polyetherimide hyperbranched …
-
"Part A. Functional Modular Phenylacetylene Units: A ""Molecular Turnstile."" Part B. Progress Towards an Electrochemically Active 9-Phenylcarbazole Hyperbranched Polymer"
Part B. Progress towards a new family of hyperbranched polymers based on the condensation of an AB$\sb2$ 9-phenylcarbazole monomer 169 has been described. Initial condensation reactions have provided material of greater than 100,000 mw as determined by GPC. No estimate of the degree of branching …
-
Combinatorics and Modelling of Highly Branched Polymers
Highly branched polymers such as dendrimers and hyperbranched polymers have a found a variety of chemical applications owing to their unique structural and functional properties, but in many cases are still lacking sufficient theoretical characterization. This thesis takes marginal steps toward …
-
Synthesis and Characterization of Multiphase, Highly Branched Polymers
… is frequently cited as a key application for hyperbranched polymers. However, the high degree of branching in these polymers restricts entanglement and the resultant mechanical properties suffer. Longer distances between branch points may allow entanglements. Highly branched polymers, where …
-
Hyperbranched And Polydimethylsiloxane Based Membranes For CO2 Capture
… possible membranes: composite layer membranes, hyperbranched membranes and dense film membranes. In addition to examining the permeance of each type, the study explored various membrane formation techniques and how that affects the permeability of specific membrane types.</p> <p>The results …
-
Synthesis and Characterization of Branched Macromolecules for High Performance Elastomers, Fibers, and Films
An A2 + B3 polymerization for the synthesis of hyperbranched polymers was altered using oligomeric precursors in place of either one or both of the monomer pairs to synthesize highly branched macromolecules. Unique topologies that are intermediates between long-chain branched and hyperbranched …
-
Synthesis and Characterization of Multicomponent Polyesters via Step-growth Polymerization
… compatibility with other substrates. However, polymers containing ionic groups always exhibit complicated behavior due to the presence of ionic aggregates in the organic matrix, and this thesis investigates the effect of backbone architectures on the properties of PET ionomers in detail. Three …
-
Understanding barriers to efficient nucleic acid delivery with bioresponsive block copolymers
… study of three classes of bioresponsive polymers for nucleic acid delivery. A central theme of the study was understanding how the structure of the polymers impacted each of the intracellular steps of delivery, rather than solely the end result. A powerful tool for efficiently quantifying …
-
Synthesis and supramolecular assembly of biomimetic polymers
… chemistry is the synthesis of macromolecules and polymers with precise shapes and architectures. Polymer microstructure and architecture strongly affect the resulting functionality of advanced materials, yet understanding the static and dynamic properties of these complex macromolecules in bulk …
-
Improved Tools for Local Hamiltonians
… trees in the plane and for certain models of hyperbranched polymers in 3D. In chapter 3 we relax the conditions on the Hamiltonian and no longer require a spectral gap or geometric locality, and we consider an approximation problem for the spectrum of the local Hamiltonian. We give a simple …
-
Synthesis and characterization of hyperbranched poly(urea-urethane)s
The thesis aims to synthesize hyperbranched poly(urea-urethane) polymers (HPU) in one-pot method using commercially available monomers which are 2,4-toluylene diisocyanate (TDI) as aromatic diisocyanate and isophorone diisocyanate (IPDI) and 2(3-isocyanatopropyl) cyclohexylisocyanate (IPCI) as …
-
Part I: Synthesis of Aromatic Polyketones Via Soluble Precursors Derived from Bis(A-Amininitrile)S; Part Ii: Modifications of Epoxy Resins with Functional Hyperbranched Poly(Arylene Ester)s
… backbone, only low to medium molecular weight polymers were obtained. The model studies proved that the carbanions of the aminonitriles can react with ether linkages to form more stable phenoxide anions and cause the termination of the polymerization. Part II: Functional hyperbranched …
-
Synthesis and applications of core functional hyperbranched polyglycerol
… the synthesis of a new alkyne core functional hyperbranched polyglycerol and describes their use as potential monomolecular imprinting materials and increasing the photostability of fluorescent dyes. The first chapter describes two methods for the synthesis of the polymers and its formal [3+2] …
-
Hybride von Metall-Nanopartikeln mit hochverzweigten Polyethylenimin als lösliche, abtrennbare Katalysatoren
… of low-molecular weight surfactants or linear polymers on the nanoparticle surface. Recently, motivated by the challenge of efficient nanoparticle stabilization and the concept of particle size control by means of synthesis in a confined environment, hybrids of dendrimers with metal …
-
Hyperbranched polyesters for polyurethane coatings: their preparation, structure and crosslinking with polyisocyanates
In this work, hyperbranched aromatic polyesters-polyphenols based on 4,4-bis(4’ hydroxy¬phenyl)pentanoic acid (BHPPA) were prepared and, according to the authors knowledge, for the first time tested as precursors for polyurethane bulk resins and coatings. Comparison of poly-BHPPA with competing …
-
Synthesis and characterization of bis-MPA based branched polymers with thymine core
Synthesis and characterisation of the bis-MPA based branched materials was performed. Thymine derivative was incorporated into the polymer structure as a core moiety and an active centre for H-bonding. The formation of assemblies was investigated.
Page 1 of 2