TY - JOUR

T1 - On the mutual relationships between molecular probe mobility and free volume and polymer dynamics in organic glass formers

T2 - Cis-1,4-poly(isoprene)

AU - Švajdlenková, Helena

AU - Šauša, Ondrej

AU - Adichtchev, Sergey V.

AU - Surovtsev, Nikolay V.

AU - Novikov, Vladimir N.

AU - Bartoš, Josef

N1 - Funding Information: Funding: This research was funded by the VEGA Agency, Slovakia with Grants No. 2/0005/20 (J.B.) and No. 2/0157/17 (O.Š.) as well as by the Slovak Research and Development Agency (SRDA) with Grant APVV-16-0369. This work was also supported by State assignment No. AAAA-A17-117052410033-9. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/1/2

Y1 - 2021/1/2

N2 - We report on the reorientation dynamics of small spin probe 2,2,6,6-tetramethylpiperidi-nyl-1-oxyl (TEMPO) in cis-1,4-poly(isoprene) (cis-1,4-PIP10k) from electron spin resonance (ESR) and the free volume of cis-1,4-PIP10k from positron annihilation lifetime spectroscopy (PALS) in relation to the high-frequency relaxations of cis-1,4-PIP10k using light scattering (LS) as well as to the slow and fast processes from broadband dielectric spectroscopy (BDS) and neutron scattering (NS). The hyperfine coupling constant, 2Azz’(T), and the correlation times, τc(T), of cis-1,4-PIP10k/TEMPO system as a function of temperature exhibit several regions of the distinct spin probe TEMPO dynamics over a wide temperature range from 100 K up to 350 K. The characteristic ESR temperatures of changes in the spin probe dynamics in cis-1,4-PIP10k/TEMPO system are closely related to the characteristic PALS ones reflecting changes in the free volume expansion from PALS measurement. Finally, the time scales of the slow and fast dynamics of TEMPO in cis-1,4-PIP10k are compared with all of the six known slow and fast relaxation modes from BDS, LS and NS techniques with the aim to discuss the controlling factors of the spin probe reorientation mobility in polymer, oligomer and small molecular organic glass-formers.

AB - We report on the reorientation dynamics of small spin probe 2,2,6,6-tetramethylpiperidi-nyl-1-oxyl (TEMPO) in cis-1,4-poly(isoprene) (cis-1,4-PIP10k) from electron spin resonance (ESR) and the free volume of cis-1,4-PIP10k from positron annihilation lifetime spectroscopy (PALS) in relation to the high-frequency relaxations of cis-1,4-PIP10k using light scattering (LS) as well as to the slow and fast processes from broadband dielectric spectroscopy (BDS) and neutron scattering (NS). The hyperfine coupling constant, 2Azz’(T), and the correlation times, τc(T), of cis-1,4-PIP10k/TEMPO system as a function of temperature exhibit several regions of the distinct spin probe TEMPO dynamics over a wide temperature range from 100 K up to 350 K. The characteristic ESR temperatures of changes in the spin probe dynamics in cis-1,4-PIP10k/TEMPO system are closely related to the characteristic PALS ones reflecting changes in the free volume expansion from PALS measurement. Finally, the time scales of the slow and fast dynamics of TEMPO in cis-1,4-PIP10k are compared with all of the six known slow and fast relaxation modes from BDS, LS and NS techniques with the aim to discuss the controlling factors of the spin probe reorientation mobility in polymer, oligomer and small molecular organic glass-formers.

KW - BDS

KW - Cis-1,4-poly(isoprene), PALS

KW - ESR

KW - TEMPO

KW - cis-1

KW - LS

KW - PALS

KW - 4-poly(isoprene)

UR - http://www.scopus.com/inward/record.url?scp=85099878731&partnerID=8YFLogxK

U2 - 10.3390/polym13020294

DO - 10.3390/polym13020294

M3 - Article

C2 - 33477605

AN - SCOPUS:85099878731

VL - 13

SP - 1

EP - 24

JO - Polymers

JF - Polymers

SN - 2073-4360

IS - 2

M1 - 294

ER -