Effect of secondary relaxation transitions on photo-induced anisotropy in glassy azobenzene-functionalized polymers

2017 ◽  
Vol 5 (27) ◽  
pp. 6828-6833 ◽  
Author(s):  
Sergey S. Kharintsev ◽  
Ksenia L. Shukhina ◽  
Alexandr I. Fishman ◽  
Semion K. Saikin
Keyword(s):  
Amorphous Polymers ◽  
Relaxation Transition ◽  
Temperature Behavior ◽  
Functionalized Polymers ◽  
Side Chain ◽  
Induced Anisotropy ◽  
Secondary Relaxation ◽  
Relaxation Transitions ◽  
Β Relaxation ◽  
Infrared Dichroism

The β-relaxation transition in side-chain azobenzene-functionalized amorphous polymers can be directly found from the temperature behavior of infrared dichroism.

On the theory of infrared dichroism of oriented amorphous polymers

1973 ◽  
Vol 6 (6) ◽  
pp. 853-857
Author(s):  
G. M. Bartenev ◽  
A. A. Valishin
Keyword(s):  
Amorphous Polymers ◽  
Infrared Dichroism

Reversible covalent locking of a supramolecular hydrogel via UV-controlled anthracene dimerization

2021 ◽  
Author(s):  
Zhanyao Hou ◽  
Werner M. Nau ◽  
Richard Hoogenboom
Keyword(s):  
Ternary Complexes ◽  
Functionalized Polymers ◽  
Side Chain ◽  
Supramolecular Hydrogel ◽  
Reversible Dimerization ◽  
Reversible Covalent

The formation of supramolecular hydrogels is demonstrated based on ternary complexes between anthracene side-chain functionalized polymers and macrocyclic hosts. Photo-induced reversible dimerization enables switching between supramolecular and covalent hydrogels.

.alpha.-Relaxation in the Glass Transition Range of Amorphous Polymers. 1. Temperature Behavior across the Glass transition

1995 ◽  
Vol 28 (5) ◽  
pp. 1516-1527 ◽  
Author(s):  
A. Alegria ◽  
E. Guerrica-Echevarria ◽  
L. Goitiandia ◽  
I. Telleria ◽  
J. Colmenero
Keyword(s):  
Glass Transition ◽  
Amorphous Polymers ◽  
Temperature Behavior ◽  
Transition Range ◽  
Glass Transition Range

Secondary relaxation transitions in alkali silicate glasses

1980 ◽  
Vol 38-39 ◽  
pp. 515-520 ◽  
Author(s):  
V.A Stepanov ◽  
V.A Bershtein ◽  
Y.A Emelyanov
Keyword(s):  
Silicate Glasses ◽  
Secondary Relaxation ◽  
Relaxation Transitions ◽  
Alkali Silicate

Study of the Molecular Mobility of Polysaccharide Solid Thin Layers by Dielectric Relaxation Spectroscopy

1997 ◽  
Vol 500 ◽  
Author(s):  
K. Liedermann ◽  
L. Lapčík ◽  
S. Desmedt
Keyword(s):  
Dielectric Relaxation ◽  
Low Frequency ◽  
Thin Layers ◽  
Side Chain ◽  
Relaxation Processes ◽  
Dielectric Relaxation Spectroscopy ◽  
Frequency Range ◽  
Polar Groups ◽  
Calculated Activation Energy ◽  
Β Relaxation

ABSTRACTTemperature dependence of measured dielectric relaxation spectra (DRS) in the frequency range 20 Hz - 1 MHz of hydroxyethylcellulose (HEC) are in the temperature range 100 – 350 K. of Arrhenius character with one relaxation process at 150 – 250 K. This process reflects most probably β-relaxation of the side chain groups. Calculated activation energy of this process was 5730 kJ/mole. Four types of polysaccharides were studied at 293 K temperature: hyaluronic acid (HA), chondroitin sulfate (CHS), HEC and carboxymethylcellulose (CMC), in the low-frequency range 10−5 - 100 Hz. Measured dielectric spectra were interpreted as sum of one A.C. conductivity process and of up to two relaxation processes. The relaxation processes were described by means of the Havriliak-Negami formula and their parameters were related to the molecular structure of the polymers. The low value of a in CHS is related to its strong coupling due to the presence of two polar groups in its monomeric unit, whereas low values of α × β are interpreted as being due to the strong steric hindrances caused by long pendants present in HEC.

Temperature behavior of secondary relaxation dynamics in tripropylene glycol

2005 ◽  
Vol 71 (17) ◽  
Author(s):  
S. Pawlus ◽  
S. Hensel-Bielowka ◽  
K. Grzybowska ◽  
J. Zioło ◽  
M. Paluch
Keyword(s):  
Temperature Behavior ◽  
Relaxation Dynamics ◽  
Secondary Relaxation
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