Relaxation processes of some aromatic sulfides, sulfoxides, and sulfones in a polystyrene matrix

1980 ◽  
Vol 73 (7) ◽  
pp. 3460-3466 ◽  
Author(s):  
M. A. Desando ◽  
S. Walker ◽  
W. H. Baarschers
Keyword(s):  
Relaxation Processes ◽  
Polystyrene Matrix

Dielectric relaxation processes of some dialkyl disulfides

1983 ◽  
Vol 61 (9) ◽  
pp. 2107-2111 ◽  
Author(s):  
H. A. Khwaja ◽  
S. Walker
Keyword(s):  
Dielectric Relaxation ◽  
Relaxation Processes ◽  
Alkyl Chains ◽  
Polystyrene Matrix ◽  
Segmental Relaxation ◽  
Higher Temperature ◽  
Dialkyl Disulfides ◽  
Intramolecular Rotation ◽  
Two Temperature ◽  
Low Temperature Process

Dielectric relaxation studies have been performed for dimethyl, diethyl, di-isopropyl, di-n-butyl, di-tert-butyl, and di-n-octyl disulfides in a polystyrene matrix. For the last five compounds the absorption appears in two temperature regions. The relaxation data for the higher temperature regions are consistent with intramolecular rotation around the S—S bond with accompanying flexibility in the alkyl chains. The enthalpy barrier to this relaxation process is ~29 kJ mol−1 and is the trans (lower) barrier. This value is typical for all six dialkyl disulfides. The most likely interpretation of the low temperature process is that there is segmental relaxation of the alkyl chains which also involves movement of the main dipoles (S—S and S—C).

Activation energy of relaxation processes in chalcogenide glasses

2013 ◽  
Vol 34 (0) ◽  
pp. 59-63
Author(s):  
А. А. Горват ◽  
В. М. Кришеник ◽  
А. Е. Кріштофорій ◽  
В. В. Мінькович ◽  
О. А. Молнар
Keyword(s):  
Activation Energy ◽  
Chalcogenide Glasses ◽  
Relaxation Processes

Features of radiothermoluminescence of polypropylene and ethylene propylenediene elastomer SKEPT-4044 compositions with nanoscale metal-containing fillers

2020 ◽  
pp. 66-73
Author(s):  
A.M. Magerramov ◽  
◽  
N.I. Kurbanova ◽  
M.N. Bayramov ◽  
N.A. Alimirzoyeva ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Molecular Mobility ◽  
Fe3o4 Nanoparticles ◽  
Low Temperatures ◽  
Frost Resistance ◽  
Relaxation Processes ◽  
Ethylene Propylene ◽  
Temperature Range ◽  
Β Relaxation

Using radiothermoluminescence (RTL), the molecular mobility features in the temperature range of 77-300 K were studied for the polypropylene (PP)/ethylene propylene diene elastomer SKEPT-4044 with NiO, Cu2O and Fe3O4 nanoparticles (NPs) based on ABS-acrylonitrile butadiene or SCS-divinyl styrene matrices. It has been shown that the introduction of nanofillers in PP significantly affects the nature and temperature of γ- and β-relaxation processes, while the region of manifestation of the β-process noticeably shifts to the region of low temperatures. Composites with Cu2O NPs have a higher β-transition temperature Tβ than composites with other NPs. It was found that PP/SKEPT-4044 composites with Cu2O NPs with a dispersion of 11-15 nm and acrylonitrile butadiene thermoplastics have optimal frost resistance compared to other compositions.

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