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Effect of Dendritic Side Groups on the Mobility of Modified Poly(epichlorohydrin) Copolymers

  • Identification data

    Identifier: imarina:9217012
    Authors:
    Teruel-Juanes, RPascual-Jose, BGraf, RReina, J AGiamberini, MRibes-Greus, A
    Abstract:
    The macromolecular dynamics of dendronized copolymer membranes (PECHs), obtained by chemical modification of poly(epichlorohydrin) with the dendron 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, was investigated. In response to a thermal treatment during membrane preparation, these copolymers show an ability to change their shape, achieve orientation, and slightly crystallize, which was also observed by CP-MAS NMR, XRD, and DSC. The phenomenon was deeply analyzed by dielectric thermal analysis. The dielectric spectra show the influence of several factors such as the number of dendritic side groups, the orientation, their self-assembling dendrons, and the molecular mobility. The dielectric spectra present a sub-Tg dielectric relaxation, labelled as γ, associated with the mobility of the benzyloxy substituent of the dendritic group. This mobility is not related to the percentage of these lateral chains but is somewhat hindered by the orientation of the dendritic groups. Unlike other less complex polymers, the crystallization was dismantled before the appearance of the glass transition (αTg). Only after that, clearing transition (αClear) can be observed. The PECHs were flexible and offered a high free volume, despite presenting a high degree of modifications. However, the molecular mobility is not independent in each phase and the self-assembling dendrons can be eventually fine-tuned according to the percentage of grafted groups.
  • Others:

    Author, as appears in the article.: Teruel-Juanes, R; Pascual-Jose, B; Graf, R; Reina, J A; Giamberini, M; Ribes-Greus, A
    Department: Química Analítica i Química Orgànica Enginyeria Química
    e-ISSN: 2073-4360
    URV's Author/s: Giamberini, Marta / Reina Lozano, José Antonio
    Keywords: Xrd Segmental dynamics Poly(epichlorohydrin) Macromolecular cooperativity Macromolecular coopera-tivity Dsc Dielectric relaxation spectra Dendronized liquid crystal membranes Crystalline polymeric wires Cp-mas nmr Broadband dielectric spectroscopy xrd viscosity units temperature-dependence state selective proton transport segmental dynamics relaxation processes poly(epichlorohydrin) macromolecular cooperativity ion-conducting membranes family dsc dielectric relaxation spectra design dendronized liquid crystal membranes cp-mas nmr
    Abstract: The macromolecular dynamics of dendronized copolymer membranes (PECHs), obtained by chemical modification of poly(epichlorohydrin) with the dendron 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, was investigated. In response to a thermal treatment during membrane preparation, these copolymers show an ability to change their shape, achieve orientation, and slightly crystallize, which was also observed by CP-MAS NMR, XRD, and DSC. The phenomenon was deeply analyzed by dielectric thermal analysis. The dielectric spectra show the influence of several factors such as the number of dendritic side groups, the orientation, their self-assembling dendrons, and the molecular mobility. The dielectric spectra present a sub-Tg dielectric relaxation, labelled as γ, associated with the mobility of the benzyloxy substituent of the dendritic group. This mobility is not related to the percentage of these lateral chains but is somewhat hindered by the orientation of the dendritic groups. Unlike other less complex polymers, the crystallization was dismantled before the appearance of the glass transition (α<sub>Tg</sub>). Only after that, clearing transition (α<sub>Clear</sub>) can be observed. The PECHs were flexible and offered a high free volume, despite presenting a high degree of modifications. However, the molecular mobility is not independent in each phase and the self-assembling dendrons can be eventually fine-tuned according to the percentage of grafted groups.
    licence for use: https://creativecommons.org/licenses/by/3.0/es/
    Author's mail: marta.giamberini@urv.cat joseantonio.reina@urv.cat
    Author identifier: 0000-0001-8278-3552 0000-0002-9245-4135
    Record's date: 2024-11-02
    Papper version: info:eu-repo/semantics/publishedVersion
    Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
    Papper original source: Polymers . 13 (12): 1961-
    APA: Teruel-Juanes, R; Pascual-Jose, B; Graf, R; Reina, J A; Giamberini, M; Ribes-Greus, A (2021). Effect of Dendritic Side Groups on the Mobility of Modified Poly(epichlorohydrin) Copolymers. Polymers , 13(12), 1961-. DOI: 10.3390/polym13121961
    Entity: Universitat Rovira i Virgili
    Journal publication year: 2021
    Publication Type: Journal Publications
  • Keywords:

    Xrd
    Segmental dynamics
    Poly(epichlorohydrin)
    Macromolecular cooperativity
    Macromolecular coopera-tivity
    Dsc
    Dielectric relaxation spectra
    Dendronized liquid crystal membranes
    Crystalline polymeric wires
    Cp-mas nmr
    Broadband dielectric spectroscopy
    xrd
    viscosity
    units
    temperature-dependence
    state
    selective proton transport
    segmental dynamics
    relaxation processes
    poly(epichlorohydrin)
    macromolecular cooperativity
    ion-conducting membranes
    family
    dsc
    dielectric relaxation spectra
    design
    dendronized liquid crystal membranes
    cp-mas nmr
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