Dielectric spectroscopy of diglycidyl ether of bisphenol-A at glass transition temperature  

作　　者：Soheil Sharifi 

机构地区：[1]Department of Physics, University of Sistan and Baluchestan, Zahedan, Iran

出　　处：《Natural Science》2012年第2期136-141,共6页自然科学期刊（英文）

摘　　要：We used broadband dielectric spectroscopy in the frequency range from 10–2 Hz up to 107 Hz and we found dynamics of the primary α- and intermolecular Johari-Goldstein (JG) β-processes are strongly correlated in diglycidyl ether of bisphenol-A over a wide temperature from 193 to 283K and pressure P range from 0.1 to 600 MPa. Analysing the temperature and pressure behavior of the α - and (JG) β-processes, a clear correlation has been found between the structural relaxation time, the Johari-Goldstein relaxation time and the dispersion of the structural relaxation. These results support the idea that the Johari-Goldstein relaxation acts as a precursor of the structural relaxation and therefore of the glass transition phenomenon.We used broadband dielectric spectroscopy in the frequency range from 10–2 Hz up to 107 Hz and we found dynamics of the primary α- and intermolecular Johari-Goldstein (JG) β-processes are strongly correlated in diglycidyl ether of bisphenol-A over a wide temperature from 193 to 283K and pressure P range from 0.1 to 600 MPa. Analysing the temperature and pressure behavior of the α - and (JG) β-processes, a clear correlation has been found between the structural relaxation time, the Johari-Goldstein relaxation time and the dispersion of the structural relaxation. These results support the idea that the Johari-Goldstein relaxation acts as a precursor of the structural relaxation and therefore of the glass transition phenomenon.

关 键 词：DIELECTRIC RELAXATION NANO-SIZE MOTION SECONDARY RELAXATION PRESSURE and Temperature 

分 类 号：O6[理学—化学]