This title appears in the Scientific Report :
2015
Please use the identifier:
http://dx.doi.org/10.1063/1.4929693 in citations.
Please use the identifier: http://hdl.handle.net/2128/17311 in citations.
Effects of configurational changes on molecular dynamics in polyvinylidene fluoride and poly(vinylidene fluoride-trifluoroethylene) ferroelectric polymers
Effects of configurational changes on molecular dynamics in polyvinylidene fluoride and poly(vinylidene fluoride-trifluoroethylene) ferroelectric polymers
We present a comparative study of proton dynamics in unpoled non-ferroelectric polymer polyvinylidene fluoride (PVDF) and in its trifluoroethylene containing ferroelectric copolymer (with 70/30 molar proportion), using quasi-elastic neutron scattering. The neutron data reveal the existence of two di...
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Personal Name(s): | Jalarvo, N. (Corresponding author) |
---|---|
Pramanick, A. / Do, C. / Diallo, S. O. | |
Contributing Institute: |
Neutronenstreuung; ICS-1 JCNS-SNS; JCNS-SNS Neutronenstreuung; JCNS-1 |
Published in: | Applied physics letters, 107 (2015) 8, S. 082907 |
Imprint: |
Melville, NY
American Inst. of Physics
2015
|
DOI: |
10.1063/1.4929693 |
Document Type: |
Journal Article |
Research Program: |
Soft Matter, Health and Life Sciences Jülich Centre for Neutron Research (JCNS) Functional Macromolecules and Complexes |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/17311 in citations.
We present a comparative study of proton dynamics in unpoled non-ferroelectric polymer polyvinylidene fluoride (PVDF) and in its trifluoroethylene containing ferroelectric copolymer (with 70/30 molar proportion), using quasi-elastic neutron scattering. The neutron data reveal the existence of two distinct types of molecular motions in the temperature range investigated. The slower motion, which is characterized in details here, is ascribed to protons jump diffusion along the polymeric carbon chains, while the faster motion could be attributed to localized rotational motion of methylene groups. At temperatures below the Curie point (Tc ∼ 385 K) of the composite polymer, the slower diffusive mode experiences longer relaxation times in the ferroelectric blend than in the bare PVDF, although the net corresponding diffusion coefficient remains comparatively the same in both polymers with characteristic activation energy of EA ≈ 27–33 kJ/mol. This arises because of a temperature dependent jump length r 0, which we observe to be effectively longer in the copolymer, possibly due to the formation of ordered ferroelectric domains below Tc . Above Tc , there is no appreciable difference in r 0 between the two systems. This observation directly relates the known dependence of Tc on molar ratio to changes in r 0, providing fundamental insight into the ferroelectric properties of PVDF-based copolymers. |