Morphological Trends in Precise Acid- and Ion-Containing Polyethylenes at Elevated Temperature

Buitrago, C. Francisco; Alam, Todd M.; Opper, Kathleen L.; Aitken, Brian S.; Wagener, Kenneth B.; Winey, Karen I.

doi:10.1021/ma4013175

Cited by 44 publications

(69 citation statements)

References 31 publications

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“…X‐ray scattering was performed at the multiangle X‐ray scattering (MAXS) facility at the University of Pennsylvania. Details of the MAXS facility can be found in Buitrago et al Data reduction and analysis were performed using the Datasqueeze software . X‐ray scattering profiles were rescaled such that all intensities were equal at q = 10.0 nm −1 , where no peaks are present, so that peak intensities could be compared.…”

Section: Methodsmentioning

confidence: 99%

High Melting Precision Sulfone Polyethylenes Synthesized by ADMET Chemistry

Gaines

Trigg

Winey

et al. 2016

Macromol. Chem. Phys.

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A series of aliphatic polysulfones is synthesized via ADMET polymerization in which a sulfone group is located precisely after every 8th, 14th, and 20th carbon. Primary structural characterization is accomplished using 1H NMR, 13C NMR, and IR. Polymer morphology is studied by DSC and X‐ray scattering, which reveals layered morphologies comprised of polyethylene crystallites along with sulfone groups arranged in sheets. In contrast to other precision polymers with functional groups synthesized by ADMET, this morphology is found at all spacer lengths. Prior to hydrogenation the sulfone polymers show Tm decreasing with increasing sulfone concentration, a typical phenomenon attributed to the mix of cis and trans configurations producing defects in the crystals. However, following hydrogenation, the melting temperature increases as the sulfone group concentration increased rather than decreased, with the highest Tm being 175 °C. This is an increase of 45 °C relative to linear polyethylene synthesized via ADMET chemistry. The precise location of the sulfone groups, which are not tactic, within these polyethylenes increases crystallinity, promotes secondary bonding and increases Tm.

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Section: Methodsmentioning

confidence: 99%

High Melting Precision Sulfone Polyethylenes Synthesized by ADMET Chemistry

Gaines

Trigg

Winey

et al. 2016

Macromol. Chem. Phys.

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“…[1][2][3] The idea of incorporating ions into a polymer structure was applied for different polymers such as polyisobutylene, 4 polystyrenes, 5 or polyethylenes. 6 A large variety of ions were investigated such as sodium cations, 7 quaternary ammoniums 8 and phosphoniums. 9 However, by bearing these ions in their structures, ion-containing polymers exhibit other advantages besides the changes in the rheological and mechanical properties: they are good conductors, selective carriers, antistatic, and antimicrobial materials.…”

Section: Introductionmentioning

confidence: 99%

Rheological study of quaternary ammonium‐containing star‐shaped polylactic acid

Belkhir

Majesté

Jegat

et al. 2019

J of Applied Polymer Sci

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Quaternary ammonium-containing star-shaped polylactic acid (PLA-Q) is analyzed in melt rheology and found to follow a clustering behavior. The viscosity of this polymer is largely higher than its analog, of the same structure, without ammonium ions. This difference is attributed to physical interactions taking place between the ammoniums and hindering the flow of the melt polymer. The frequency sweeps of the storage (G 0 ) and loss (G 00 ) modulus of the melt PLA-Q are achieved at different temperatures and different shearing times. The iso-temperature and iso-time superposition of the resulting curves were achieved using, respectively, a temperature and a time shift factors, this superposition allowed the determination of the flow activation energy; its value corresponds to an ionic process confirming the ionic interactions. When the two shift factors are used simultaneously, a unique master curve of both G 0 and G 00 is obtained; this curve follows the Rouse model indicating the presence of two types of ionic associations within the melt polymer: a large number of multiplets having small size and a small number of clusters of larger size.

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“…demonstrated that the folding behavior of polyethylene‐like polymers can be controlled by placing bulky substituents at periodically along the polymer backbone, which served as a folding controller . Similarly, research groups of Wagener, Winey, Mecking, and others studied folding of polyethylene‐like chains by periodic placement of hexyl, oligoethylene glycol, sulfonate or even chloro‐ substituents, along the backbone . They also demonstrated the profound effect of periodicity of the substituent on the folding behavior and the lamellar dimensions; in case of randomly distributed branch points, the polymers were found to exhibit curved and segmented morphologies .…”

Section: Introductionmentioning

confidence: 96%

Criss‐cross amphiphilic polymers and analogous model systems

Chakraborty

Ramakrishnan

2018

J. Polym. Sci. Part A: Polym. Chem.

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A new class of amphiphilic polymers carrying two pendant docosyl (C22) chains, located at periodic intervals that are separated by PEG chains of varying lengths, was synthesized via a simple melt‐transesterification polymerization, using dimethyl, 2,5‐didocosyloxyterephthalate as one of the monomers. DSC, variable temperature FT‐IR, and WAXS studies demonstrated that immiscibility between the pendant docosyl units and the backbone PEG segments drives their self‐segregation; this results in the crystallization of the pendant docosyl segments and the generation of a lamellar morphology with the alkyl segments and the PEG chains occupying alternate layers. Based on the study of model criss‐cross amphiphiles that resemble the polymer repeat unit, it is postulated that the chains reconfigure such that both the docosyl chains fold to one side of the terephthalate unit while the PEG segments form a loop on the other side; these chains then organize in a bilayer to form the lamellar structure. The simplicity of the synthesis and the rather unique properties of these polymers suggests that such a design could be translated to develop other interesting functional materials that could exploit the immiscibility‐driven microphase separation for the generation of sub‐10 nm domains; these could have potential applications, such as in membranes, solid polymer electrolyte formulations, and so forth. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1554–1563

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Morphological Trends in Precise Acid- and Ion-Containing Polyethylenes at Elevated Temperature

Cited by 44 publications

References 31 publications

High Melting Precision Sulfone Polyethylenes Synthesized by ADMET Chemistry

High Melting Precision Sulfone Polyethylenes Synthesized by ADMET Chemistry

Rheological study of quaternary ammonium‐containing star‐shaped polylactic acid

Criss‐cross amphiphilic polymers and analogous model systems

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