Dielectric relaxation behaviour of poly(ethylene naphthalene 2,6 dicarboxylate) (PEN)

Tie molecules, morphology and confinement effects in semi – crystalline poly(ethylene naphthalene-2,6-dicarboxylate) (PEN)

“…The relaxation phenomena in amorphous and semi-crystalline PEN have been previously investigated by means of dynamic mechanical analysis (DMA) and dielectric relaxation spectroscopy (DRS) [4][5][6][7] . Three relaxation processes: ,  * and  have been observed in order of increasing temperatures: -The -relaxation can be observed at around -20°C for a frequency of 1 kHz.…”

“…This process was assigned to the out of plane motions of the naphthalene cycle by Bellomo et al 36 and more precisely to the motions within nano-scale aggregates of naphthalene rings motions 4,6,7,37,38 . In the frequency/temperature region of the * process, the contribution of motions within liquid-crystalline nanodomains are also reported after crystallization from the molten state 42 which can complicate the exact attribution of the * process.…”

“…Therefore, this paper will deal mainly with the study of α-process in PEN as a function of crystallization conditions. Previous works have shown that -relaxation of PEN classically shifts to higher temperatures as the result of the confinement of the amorphous phase by the crystalline phase [4][5][6][7] . In addition to the development of the semi-crystalline morphology, a structuration of the amorphous phase is likely to occur with the formation of a rigid amorphous phase, i.e.…”

“…The molecular mobility in semi-crystalline polymers has been studied by several authors using a large number of systems and spectroscopic methods [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] . However, there are still few works analyzing simultaneously in details their molecular and nano structure in relation with their dynamics [9][10][11][12] .…”

The storage and its stability of space charge in poly(ethylene naphthalene-2,6-dicarboxylate)

“…Thus it is argued to be used as a serious candidate for PET substitution in a large number of applications [1] , and attracts extensive interest of researchers. Indeed, there is a considerable quantity of literatures available on the dielectric and dynamic mechanical properties of PEN [2][3][4][5][6][7][8] . Among these literatures Canadas et al [5] studied the space charge relaxation (ρ relaxation) of PEN by TSD method and calculated relative parameters, but the information on the space charge storage and its stability is still lacking, which is known to be of much importance for dielectrics and electrical insulation, especially for electret applications.…”