Premium
Molecular Dynamics of Poly(ethylene‐2,5‐furanoate) (PEF) as a Function of the Degree of Crystallinity by Dielectric Spectroscopy and Calorimetry
Author(s) -
Dimitriadis Theodoros,
Bikiaris Dimitrios N.,
Papageorgiou George Z.,
Floudas George
Publication year - 2016
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.201600278
Subject(s) - crystallinity , differential scanning calorimetry , materials science , amorphous solid , crystallization , dielectric , annealing (glass) , glass transition , relaxation (psychology) , polymer chemistry , chemical engineering , composite material , analytical chemistry (journal) , polymer , chemistry , crystallography , thermodynamics , organic chemistry , physics , psychology , social psychology , optoelectronics , engineering
The segmental and local dynamics of the bio‐based polyester poly(ethylene‐2,5‐furanoate) (PEF) are investigated by dielectric spectroscopy (DS) at atmospheric pressure as a function of temperature and frequency for samples prepared with different degrees of crystallinity. Crystallization significantly alters the segmental process as this is manifested in the dielectric strength and the distribution of relaxation times. Enhanced crystallinity by the different annealing protocols increases the glass temperature of the mobile amorphous fraction. A two‐phase model is adequate in describing the dynamics associated with the β ‐process within the glassy state. However, the same model fails in describing the segmental dynamics at and above the glass temperature. The combined differential scanning calorimetry and DS results provide evidence that for samples with a degree of crystallinity of ≈40%, approximately a third of segments are located within the restricted amorphous fraction.