TITLE:
Dielectric Spectroscopy of PVAc at Different Isobaric-Isothermal Paths
AUTHORS:
Soheil Sharifi
KEYWORDS:
Dielectric Relaxation; Nan-Size Motion; Pressure and Temperature
JOURNAL NAME:
Materials Sciences and Applications,
Vol.3 No.3,
March
23,
2012
ABSTRACT: We studied broadband dielectric spectroscopy of a glass from systems that the dynamics of the primary α- and the Johari-Goldstein (JG) β-processes are strongly correlated in Poly(vinyl acetate) over a wide temperature T and pressure P range. Analysing the temperature and pressure behaviour of the α- and (Non-JG) β-processes, a correlation hasnot been found between the structural relaxation time, the (Non-JG) β-processes relaxation time and the dispersion of the structural relaxation. These results support the idea that the (JG)-processes relaxation acts as a precursor of the structural relaxation and therefore of the glass transition phenomenon but it isnot clear relation in the (Non-JG) β-processes and structural relaxation at PVAc.