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About The Activation Energies Of The Main And Secondary Relaxations In Cured Styrene Butadiene Rubber

A. Ghilarducci, H. Salva, A. Marzocca
Published 2009 · Chemistry

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This article studies the influence of the network structure on the activation energies of the α and β relaxations in vulcanized styrene butadiene rubber, SBR. A cure system based on sulphur and TBBS (N-t-butyl-2-benzothiazole sulfenamide) was used in the formulation of several compounds cured at 433 K. The activation energies were evaluated from internal friction (loss tangent) data of the compounds using an automated subresonant forced pendulum in a wide frequency range and between 80 K and 273 K. The internal friction data of the samples reveal two transitions, α and β, characterized by the temperatures T α and T β , due to the glass transition and the phenyl group rotation of the copolymer, respectively. Although T α increases at higher crosslink density, it shows also a dependence with the amount of polysulphide and monosulphide linkages present in the samples. The highest activation energy for this process is obtained for the samples with high crosslink density and 30% of monosulphides in this structure. In the case of the β-relaxation, there is a pronounced change in the activation energy between the uncured and the cured samples. The type of structure formed during vulcanization has an important effect in the activation energy of the segmental mode-process. In the case of the β-process, the cis-trans isomerization that takes place during vulcanization in the butadiene part of the SBR, might be the cause of conformational changes in the surrounding of the phenyl rings that affect the energy barrier associated to the phenyl rotation.
This paper references
Phenyl Group Rotation in Polystyrene
A. Tonelli (1973)
Calculation of Phenyl Group Rotation in Polystyrene by Means of Semiempirical Potentials
P. Hägele (1977)
Solid State 13C NMR Applied to Styrene-Butadiene Rubbers Study of the Rubber Vulcanized Network Structures
L. Pellicioli (2002)
Theoretical approach to the assignment of molecular mechanisms for cryogenic loss peaks in polymers
S. Reich (1972)
Gordon S. Fulcher (1925)
A Study of Cooperative Phenyl Ring Flip Motions in Glassy Polystyrene by Molecular Simulations
R. Khare (1995)
Glass-transition and secondary relaxation in SBR-1502 from dynamic mechanical data
S. Cerveny (2000)
Effect of nature and extent of crosslinking on swelling and mechanical behavior of styrene–butadiene rubber membranes
Soney C. George (1999)
Analysis of network structure formed in styrene–butadiene rubber cured with sulfur/TBBS system
A. J. Marzocca (2007)
Die Abhängigkeit der Viscosität von der Temperatur bie unterkühlten Flüssigkeiten
G. Tammann (1926)
Recent Developments in Crosslinking of Elastomers
A. S. Aprem (2005)
Apparatus for dynamic and static measurements of mechanical properties of solids and of flux‐lattice in type‐II superconductors at low frequency (10−5–10 Hz) and temperature (4.7–500 K)
G. D'Anna (1990)
Relaxation processes in supercooled liquids
W. Gotze (1992)
Sulfur‐induced cis‐trans isomerization of polybutadiene
W. A. Bishop (1961)
An analysis of the influence of the accelerator/sulfur ratio in the cure reaction and the uniaxial stress‐strain behavior of SBR
A. J. Marzocca (2004)
Das Temperaturabhangigkeitsgesetz der Viskositat von Flussigkeiten
H. Vogel (1921)
Vulcanization kinetic of styrene–butadiene rubber by sulfur/TBBS
A. J. Marzocca (2006)
Evaluation of the polymer–solvent interaction parameter χ for the system cured styrene butadiene rubber and toluene
A. J. Marzocca (2007)
Nature of the Glass Transition and the Glassy State
J. Gibbs (1958)
The Vogel-Fulcher-Tamman Equation Investigated by Atomistic Simulation with Regard to the Adam-Gibbs Model
N. Metatla (2007)
On the Temperature Dependence of Cooperative Relaxation Properties in Glass‐Forming Liquids
G. Adam (1965)
Dependence of the network structure of cured styrene butadiene rubber on the sulphur content
W. Salgueiro (2004)
Dynamic mechanical and dielectric relaxations of polystyrene below the glass temperature
O. Yano (1971)

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