摘要
Dielectric absorption studies of H-bonded complexes of methyl methacrylate (MMA) and ethyl methacrylate (EMA) with p-cresol, p-chlorophenol, 2,4-dichlorophenol, and p-bromophenol were studied at microwave frequency 9.37 GHz in dilute solution of carbon tetrachloride at 308 K. Different dielectric parameters like dielectric constantε′ and dielectric loss ε″ at microwave frequency, static dielectric constant ε_0 and dielectric constant ε_∞ at optical frequency were determined. The validity of the single frequency equation of Higasi et al. for multiple relaxation time τ_(1) was found to be a function of the hydrogen bonding strength of phenolic hydrogen, whereas the group rotation relaxation time τ_(2) was a function of the steric interaction of proton donor. The relaxation time was the maximum at 50∶50 (molar ratio) of methacrylates with phenols.
Dielectric absorption studies of H-bonded complexes of methyl methacrylate (MMA) and ethyl methacrylate (EMA) with p-cresol, p-chlorophenol, 2,4-dichlorophenol, and p-bromophenol were studied at microwave frequency 9.37 GHz in dilute solution of carbon tetrachloride at 308 K. Different dielectric parameters like dielectric constant ε' and dielectric loss ε" at microwave frequency, static dielectric constant ε0 and dielectric constant ε∞ at optical frequency were determined. The validity of the single frequency equation of Higasi et al. for multiple relaxation time τ(1) was found to be a function of the hydrogen bonding strength of phenolic hydrogen, whereas the group rotation relaxation time τ(2) was a function of the steric interaction of proton donor. The relaxation time was the maximum at 50: 50 (molar ratio) of methacrylates with phenols.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第4期513-516,共4页
Acta Physico-Chimica Sinica
关键词
化学制品
丙烯酸酯
电介质
微波
Acrylic esters
Phenol derivatives
Dielectric relaxation
X-band microwave