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Showing 1 to 20 of 34 for “"Step-growth polymerization"”.
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Synthesis and Characterization of Multicomponent Polyesters via Step-growth Polymerization
… were synthesized using conventional melt polymerization. Solid state sodium NMR spectroscopy and melt rheological analysis demonstrated that the stability of ionic aggregates of telechelic ionomers decreased dramatically with an increase in temperature. A slightly branched structure …
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Step-Growth Polymerization Towards the Design of Polymers: Assembly and Disassembly of Macromolecules
Step-growth polymerization provided an effective method for the preparation of several high performance polymers. Step-growth polymerization was used for syntheses of poly(siloxane imides), polyesters, poly(triazole esters), poly(triazole ether esters), and epoxy networks. Each of these polymeric …
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High Performance Engineering Polymers: Design, Properties, and Performance
… for a wide range of applications. Utilizing step-growth polymerization techniques, a myriad of reaction conditions probed various polymer families including polysulfones, polyesters, polyimides and polyureas. Copolymers ranging from random to segmented sequences provided insight into the …
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Synthesis and characterization of m-aminophenoxide functionalized poly(tetramethylene oxide)
… used to initiate a bifunctional cationic living polymerization of tetrahydrofuran (THP). An anhydrous solution of m-aminophenoxide was used to terminate the polymerization, which resulted in aromatic amine telechelic PTMO of controlled molecular weight. The order of addition of the …
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Exploring Multiple Hydrogen Bonding and Ionic Bonding in the Design of Supramolecular Polymers
… hydrogen bonding (QHB) scaffolds utilizing chain-growth polymerization or step-growth polymerization, as well as elucidate the structure-property-morphology relationships of the polymers. A 2-step nucleophilic substitution reaction afforded a series of 1,4-diazabicyclo[2.2.2]octane (DABCO)-based …
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Synthesis and characterization of poly(arylene ether)s containing phosphorus, sulfur and heterocyclic pendant moieties
… demonstrate that potassium carbonate mediated step polymerizations likely proceed with etherification of one of the phenolic groups, prior to difunctional coupling, which can achieve high molecular weight. The formation of cyclic oligomers in the step-growth polymerization of poly(arylene …
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Structure and Properties of Nano- and Meso-scale Materials Prepared by Designed Self-Aasembly of Nanoparticles
… developed a method for terminating the colloidal polymerization process of gold nanorods by post-assembly photocrosslinking of polymer ligands. By functionalizing gold nanorods with a hydrophobic polymer containing pendant double bonds, we were able to compartmentalize a hydrophobic …
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Synthesis and Characterization of Poly(arylene ether sulfone)s with Novel Structures and Architectures
… dendritic terminal groups were synthesized by step-growth polymerization of two difunctional monomers in the presence of preformed dendritic end-cappers. These polymers were characterized by NMR, SEC, DSC, TGA, melt rheology and tensile tests. The melt viscosities of these polymers in the high …
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Palladium catalysis in the synthesis of polyaniline-related materials
… One method consists of a bidirectional chain growth from a symmetric core piece, whereas the other involves a divergent-convergent synthesis of nonsymmetric fragments, followed by coupling to a symmetric core fragment. The oligoaniline precursors are soluble in a variety of common organic …
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Structure-Property Relationships of Polyester Regioisomers and Pendant Functionalized Polyetherimides
Step-growth polymerization enabled the synthesis of novel polyester regioisomers and pendant functionalized polyetherimides (PEI)s. Novel monomers incorporated at targeted mol % produced series of polyesters and PEIs, suitable for systematic analysis of key polymer properties. Subsequent …
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From N to P: Examining Structure-Property Relationships of Ammonium- and Phosphonium-Containing Macromolecules
… properties. Conventional free radical polymerization readily generated a large library of ammonium- and phosphonium-containing polyelectrolytes. Along with the two different cationic atoms, the alkyl substituent lengths and counterions were varied to generate a thorough …
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Novel Poly(N-substituted glycine)s : synthesis, post-modification, and physical properties
… of bio-relevant polymers via either chain- or step-growth polymerization were targeted. A 3-step synthetic approach towards N-substituted glycine N-carboxyanhydrides (NNCA) was implemented, or developed, and optimized allowing for an efficient gram scale preparation of the aforementioned …
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Bio-inspired Design and Self-Assembly of Nucleobase- and Ion-Containing Polymers
… of supramolecular polymers using free radical polymerization and controlled radical polymerization techniques. Comprehensive investigations for the structure-property-morphology relationships of these supramolecular polymers elucidated the effect of noncovalent interactions on polymer physical …
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Designing Functionality into Step-Growth Polymers from Liquid Crystallinity to Additive Manufacturing
Step-growth polymerization facilitates the synthesis of a wide range of industrially applicable polymers, such as polyesters and polysulfones. The choice of backbone and end group structure within these polymers drastically impacts the final material properties and processability emphasizing the …
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Novel Lanthanide Containing Polymers for Nucleic Acid Delivery and Monitoring of Polyplex Dynamics
… spectroscopy). Polymers were synthesized via step-growth polymerization to achieve a degree of polymerization of 18-24 for different analogues with varying amine number (three to six, N3-N6) along the backbone. Dynamic light scattering performed on the polyplexes (polymer-DNA complexes) …
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Cyclopentadiene as a Platform for Polymer Synthesis and Modification of Macromolecular Systems
… substituent on the terminal diene rings. Polymerizations with 1,4- and 1,3-diethynylbenzene afforded linear Diels-Alder polyphenylenes (DAPPs) having lateral tert-butyl and perfluoro-4-tolyl substituents. The perfluoro-4-tolyl-substituted DAPPs are thermally stable, glassy solids (Tg ~ 230 …
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Designing Multiphase Step-Growth Polymers for Advanced Technologies: From Electromechanical Transducers to Additive Manufacturing
The synthesis and characterization of step-growth polymers with novel monomers provided materials with tailored properties for emerging technologies. Specifically, multiphase materials (i.e., microphase separated block copolymers) exploit the synergistic relationship of combining polymers with …
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Design and characterization of aromatic thermosetting copolyester resin for polymer matrix nanocomposites
… of precursor oligomers during condensation polymerization reaction regulate thermal-mechanical properties of self-generated foam morphologies. Aluminum foam layered aromatic thermosetting copolyester foam sandwich structures demonstrate outstanding impact energy absorption characteristics. …
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Synthesis and characterization of ammonium ionenes containing hydrogen bonding functionalities
… macromolecular backbone and are synthesized via step-growth polymerization technique. They offer interesting coulombic properties, and the synthetic design provides control over charge density. Non-covalent interactions including nucleobase hydrogen bonding and electrostatics were studied in …
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Synthesis of Highly Fluorinated Diels-Alder Polyphenylenes
… to lower molecular weight in corresponding polymerization reactions.
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