scholarly journals The Payne Effect in Double Network Elastomers

2005 ◽  
Vol 78 (1) ◽  
pp. 76-83 ◽  
Author(s):  
J. Wang ◽  
G. R. Hamed ◽  
K. Umetsu ◽  
C. M. Roland

Abstract Double network elastomers were prepared by curing under strain previously-crosslinked natural rubber or styrene-butadiene copolymer. The rubbers were reinforced with carbon black, so that the conventional (singly-cured) materials exhibited a substantial Payne effect, reflecting agglomeration of the filler particles. This effect was much reduced in the double networks - the storage modulus varied more weakly with strain amplitude, and the mechanical hysteresis was substantially smaller. Comparable results were obtained for dynamic mechanical measurements employing different test geometries; that is, the effect is independent of the direction of the strain relative to the orientation of the double network. These results indicate that deformation during the imposition of a second network disrupts the carbon black agglomerates, and this deflocculated structure is stabilized by the second crosslinking. Thus, double network processing is a general means to lower the hysteresis of filled rubbers.

2013 ◽  
Vol 86 (4) ◽  
pp. 572-578 ◽  
Author(s):  
Julie Diani ◽  
Yannick Merckel ◽  
Mathias Brieu ◽  
Julien Caillard

ABSTRACT The authors compared the mechanical behavior and, more precisely, the Mullins and the cyclic (post-Mullins) softenings of two filled rubbers. A crystallizing natural rubber and a noncrystallizing styrene–butadiene rubber of similar compositions resulting in similar cross-link densities and filled with 40 phr of N347 carbon-black fillers were tested in cyclic uniaxial tension at room temperature and at 85 °C. Crystallization in filled rubbers is known to increase stress at high stretch, stretch at break, cycle hysteresis, and fatigue lifetime and to reduce crack propagation. In this study, it is shown that crystallization also seems to enhance the Mullins softening (softening at the first cycle) and to favor the apparent cyclic softening. Results reveal that natural rubber shows an amplitude dependence on the cyclic softening, whereas the styrene–butadiene rubber does not. Finally, results demonstrate that studying filled rubber softening cannot help predict lifetime.


2020 ◽  
Vol 39 (1) ◽  
pp. 81-90
Author(s):  
An Zhao ◽  
Xuan-Yu Shi ◽  
Shi-Hao Sun ◽  
Hai-Mo Zhang ◽  
Min Zuo ◽  
...  

1971 ◽  
Vol 44 (1) ◽  
pp. 258-270 ◽  
Author(s):  
D. A. Meyer ◽  
J. G. Sommer

Abstract Important factors of potential use for manipulating static and dynamic stiffness and the damping characteristics of compounds based on styrene-butadiene and polybutadiene elastomers and their blends have been outlined. Their characteristics have been compared with those of IIR and EPDM compounds. The effects of variations in composition are quantitatively defined to assist the compounder in combining these effects in a manner that will lead to a desired combination of properties. In addition to the expected increase in static spring rate and dynamic spring rate with carbon black level, the following responses to compositional variations were found important: 1. The complex dynamic spring rate is more sharply dependent upon carbon black level than the static spring rate. 2. The complex dynamic spring rate is essentially independent of the level of crosslinking while static spring rate increases. 3. Damping coefficient is directly proportional to the level of carbon black and inversely proportional to the level of crosslinking. 4. Styrene level in a polymer blend and plasticizer composition can be used to adjust loss modulus and storage modulus at a given temperature and also to modify the rate of change of these properties with temperature. 5. The strain dependency of storage modulus was found in one instance to vary with the elastomer composition. The IIR vulcanizate, when formulated to the same static modulus, exhibited a larger strain dependence than the SBR, BR, and EPDM composition.


Author(s):  
Xuanyu Shi ◽  
Shihao Sun ◽  
An Zhao ◽  
Haimo Zhang ◽  
Min Zuo ◽  
...  

2007 ◽  
Vol 80 (4) ◽  
pp. 672-689 ◽  
Author(s):  
Ranimol Stephen ◽  
Sabu Thomas ◽  
K. V. S. N. Raju ◽  
Siby Varghese ◽  
Kuruvilla Joseph ◽  
...  

Abstract The viscoelastic and dielectric properties of nano structured layered silicates reinforced natural rubber (NR), carboxylated styrene butadiene rubber (XSBR) and their blends have been analyzed. The viscoelastic properties such as storage modulus, loss modulus, damping behavior and glass transition temperature of nano filled latices have been investigated. Upon the addition of filler, the storage modulus of nanocomposites was found to increase due to the enhancement in stiffness of the material. Due to the restricted mobility of polymer chain segments, the damping values decreased as a function of filler loading. An investigation of the viscoelastic properties revealed that there was a strong interaction between the polymer and the filler. Latex nanocomposites was characterized by X-ray diffraction technique. The enhanced d values indicated the intercalation of polymer chain into the layers of silicates. The dielectric properties of nanocomposites have been investigated as a function of frequency in the range of 50Hz–100KHz. The effect of frequency on dielectric permittivity (Ε′), dielectric loss (Ε″), dissipation factor (tan δ) and volume resistivity (ρv) of latex nanocomposite have been measured under alternating current. The dielectric permittivity of the samples was found to be higher upon the incorporation of nano fillers. The volume resistivity decreased due to the enhanced conductivity of filled samples.


Polymer ◽  
2019 ◽  
Vol 185 ◽  
pp. 121953 ◽  
Author(s):  
Zhongjia Xu ◽  
Yihu Song ◽  
Qiang Zheng

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