TY  - JOUR
A1  - Raman Venkatesan, Thulasinath
A1  - Gulyakova, Anna A.
A1  - Frübing, Peter
A1  - Gerhard, Reimund
T1  - Relaxation processes and structural transitions in poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) relaxor-ferroelectric terpolymers as seen in dielectric spectroscopy
JF  - IEEE transactions on dielectrics and electrical insulation
N2  - Dielectric relaxation processes and structural transitions in Poly(vinylidenefluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)) terpolymer films with two different monomer compositions were investigated in comparison with Poly(vinylidenefluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer films as reference material. Differential Scanning Calorimetry was employed to assess annealing effects on phase transitions and crystalline structure, while relaxation processes were investigated by means of Dielectric Relaxation Spectroscopy, the results of which indicate the existence of two separate dispersion regions, denoted as processes A and B, respectively. Process A appears at a certain temperature independent of frequency, but is strongly influenced by the crystallisation temperature and the CFE content, while peak B shows typical features of a relaxation process and is less influenced by crystallisation temperature and CFE content. Furthermore, peak B is related to the glass transition which is more pronounced in the terpolymer than in P(VDF-TrFE). A closer analysis indicates that the addition of CFE and thermal annealing gradually shift the ferro-to-paraelectric transition in P(VDF-TrFE) to lower temperatures, while the phase transition is transformed more and more into a relaxation.
KW  - P(VDF-TrFE-CFE) terpolymer
KW  - relaxor-ferroelectric polymer
KW  - dielectric relaxation spectroscopy
KW  - Curie transition
KW  - differential scanning calorimetry
Y1  - 2018
U6  - https://doi.org/10.1109/TDEI.2018.007440
SN  - 1070-9878
SN  - 1558-4135
VL  - 25
IS  - 6
SP  - 2229
EP  - 2235
PB  - Institut of Electrical and Electronics Engineers
CY  - Piscataway
ER  -