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 20 for “"End Capping"”.
-
Thermodynamically Driven (Reversible) End-Capping of Pseudorotaxanes to Produce Rotaxanes
… a labile bond between the guest molecule and the end stopper group. The reversibility of this bond allows for threading by the host molecule via chemical equilibrium. Intramolecular interactions such as hydrogen bonding and π-π stacking facilitate threading to form the pseudorotaxane which is …
-
Synthesis and characterisation of branched poly(ethylene terephthalate)s
… trimesic acid, and the control of branching with end-capping agents, such as benzyl alcohol. The polymers synthesised were then characterised by solution viscosity, end-group analysis, DSC analysis, theological analysis and light scattering. Extensive branching of polymers has been observed and …
-
Characterization of pi-donor chiral stationary phases through a thermodynamic study of analyte adsorption
… most probable strand spacing were found to be dependent upon surface coverages to some extent. These results are consistent with the ""patch"" model since changes in the most probable interstrand distance are much smaller than would be expected if the strands were uniformly spaced on the surface. …
-
Synthesis and Characterization of Multiblock Copolymers for Proton Exchange Membrane Fuel Cells (PEMFC)
… coupling of 2,5-dichloro-benzophenone and the end-capping agent 4-chloro-4'-fluorobenzophenone or 4-chlorophenly-4′-fluorophenyl sulfone. The molecular weights of these oligomers were readily controlled by altering the amount of end-capping agent. These telechelic oligomers (hydrophobic) were …
-
Conjugated polymer based materials via the incorporation of polymerizable units
… based materials by block copolymerization and/or end-capping with polymerizable units. In Chapter 1, three different norbornene derivatives having phenylene-heterocyclic moieties were copolymerized with either norbornene or 7-oxanorbornene derivatives via ring-opening metathesis polymerization …
-
Synthesis of Well-Defined Multi-End Functionalized Polymers via Living Anionic Polymerization
… work aimed at producing a series of multi-end functionalized polystyrene and polyisoprene additives with a wide range of molecular weights, carrying 1 to 3 fluoroalkyl groups that have been prepared by end capping the living chain ends of polymers prepared via anionic polymerization …
-
A Study of End-functionalized Polylactide based Thin Films for Biomedical Applications
… was to understand how topography and chemistry (end functionalization of PLA) of scaffolds impacts cell attachment, growth and proliferation. This was achieved by spin-coating PLA and Ionomeric PLA on glass coverslips followed by thermal annealing of these thin films that resulted in scaffolds of …
-
Impact of end groups of PLGA on polymer properties and ocular implant performance
… the risk of distortion on hydration causing endothelial contact, the biological fate of the polymeric system and the physico-chemical properties of the active compound are all issues that need to be integrated into the design. The effect of the copolymer composition and molecular weight has …
-
Chemical vapor deposition thin films as biopassivation coatings and directly patternable dielectrics
… and provided a means of selectively end-capping polymer chains present in the film structure.
-
Synthesis and characterization of poly(arylene ethers) and functionalized oligomers
Molecular weight control and endgroup functionalization in poly(arylene ether sulfones) has been achieved by two synthetic routes. The first utilizes DMSO/sodium hydroxide and aminophenol to introduce the amine functionality. This route, though synthetically useful, suffers from serious …
-
Copper-catalyzed arylation of 1,2-amino alcohols. Synthesis of N-terminal, peptide helix initiators, and characterization of highly helical, capped polyalanine peptides
… of polyalanine and helix stabilization by end capping were combined to synthesize a series of highly helical, water-soluble polyalanine peptides permitting straightforward context-free investigation of this most common helix- forming [alpha]-amino acid. Three types of peptides incorporating …
-
The design and synthesis of polymeric assemblies for materials applications : chemosensing, liquid crystal alignment and block copolymers
… In the final chapter, we describe the end-capping of cross-coupling polymerizations using the hydroarylation of norbornadiene. This reaction is shown to be an efficient approach to generating macroinitiators which can be further polymerized using ring opening metathesis polymerization. …
-
Fractional Labelmap Representation of Anatomical Structures
… such as branching, keyhole contours, and end-capping. Closed surfaces were converted into fractional labelmap representations, where each voxel represents occupancy between 0% and 100%. Existing segmentation methods were modified to allow fractional labelmaps to be edited directly. …
-
MOLECULAR MECHANISMS OF ACTIN FILAMENT ASSEMBLY AND TURNOVER
… eukaryotic kingdom powering cellular locomotion, endocytosis, mechano-transduction, and many other essential cellular functions. This versatility stems primarily from the myriads of actin binding proteins (ABPs) that bind to and regulate actin. A substantial proportion of these proteins modify …
-
Design and synthesis of ionisable amino-polyester lipid nanoparticles for extrahepatic RNA delivery
… of APEs with different linkers and end-capping amine compositions. While these modifications had minimal impact on physicochemical properties, they significantly influenced delivery outcomes. Cationic and zwitterionic linkers enhanced spleen selectivity, whereas neutral linkers with …
-
Water ingression into poly(imide-siloxane)s
… oligomers, with phthalic anhydride as an end-capping agent. Similar copolymers had been previously shown to have reduced water sorption, increased surface hydrophobicity, and increased adhesive durability in hot/wet environments. Inverse gas chromatography was used to conduct surface …
-
Stable Fluorinated Antimicrobial Coatings
… a new concept was explored by end-capping the same diol with isocyanatopropyltriethoxysilane and blending the end-capped diol with base polyurethane along with a 10 wt % cross linker. These modifiers show excellent antimicrobial properties (100% kill of bacteria) over one month …
-
Bimetallic Main-Group Catalysts for the Synthesis of Advanced Biocompatible, Biodegradable, and Sustainable Polymers
… behavior governed by the nature of the end-capping groups. First, binucleating aniline-based bis(pyrazolyl)alkane ligands were synthesized. Their corresponding neutral monoethyl monozinc complexes, as well as cationic μ-bridged dizinc complexes, were prepared and employed in the …
-
Non-covalent Intermolecular Interactions in Polymer Design: Segmented Copolymers to Non-viral Gene Delivery Vectors
… properties. A new class of non-chain extended segmented copolymers that contained both urea and oxamide hydrogen bonding groups in the hard segment were synthesized. PDMS poly(urea oxamide) (PDMS-UOx) copolymers displayed thermoplastic elastomer behavior with enhanced physical properties …
-
Synthesis and Characterization of Wholly Aromatic Semicrystalline Polyimides Based Upon Bis(4-Aminophenoxy) Benzenes
… s-biphenyl dianhydride (BPDA) produced a melting endotherm, T<sub>m</sub>, at about 395°C, which was well within the thermal stability limitations of organic materials, i.e., less than or approximately 450°C. It was also demonstrated to be important to quantitatively endcap both ends of the chains …