Practice for Styrene-Butadiene Rubber (SBR)Establishing Raw Mooney Viscosity Target Values

Abstract Changes in the value of [η], [ηm], K′, (M) and μ of SBR masticated in the cold at 25.0 ± 5.0° C in presence of oxygen with the times of mastication are reported. An empirical relation has been developed between the intrinsic viscosity [η] and Mooney viscosity [ηm] which permits molecular weight of the rubber to be determined directly from Mooney viscosity. The value of g which appears in the Flory equation connecting true crosslink density with the physically determined one has been calculated for unfilled SBR.

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Carbon Nanotubes in Tyre Rubbers. Part 3: Study of the Effect of Nanotubes in Silica-filled Tread Rubbers

International Polymer Science and Technology ◽

10.1177/0307174x1704400305 ◽

2017 ◽

Vol 44 (3) ◽

pp. 25-30

Author(s):

R.R. Batrshina ◽

A.M. Mokhnatkin ◽

V.P. Dorozhkin ◽

E.G. Mokhnatkina ◽

V.E. Muradyan ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

The Other ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Cohesion Strength ◽

Mooney Viscosity ◽

Styrene Butadiene ◽

Walled Carbon Nanotubes

The processing and mechanical properties of green and vulcanised tread rubbers based on styrene butadiene rubber and polybutadiene with the addition of natural rubbers filled with silica and containing single-walled carbon nanotubes (SCNTs) were studied. Two types of rubber were manufactured: one containing untreated SCNTs and stearic acid, ensuring the presence of – COOH groups, and the other with treated SCNTs. The properties of these composites were compared. In both cases, the introduction of SCNTs leads to an increase in the cohesion strength of the green rubber mixes, to an improvement in their vulcanisation properties, and to an increase in their Mooney viscosity. In contrast to tread rubbers filled with carbon black, in the case of filling with silica the Payne effect decreases. The dynamic and other mechanical properties of the vulcanisates change in different ways. The wear resistance, like other service properties, is improved.

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Important Stability Factors for Styrene-Butadiene Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3542170 ◽

1960 ◽

Vol 33 (2) ◽

pp. 510-527 ◽

Cited By ~ 2

Author(s):

B. A. Hunter ◽

A. C. Nawakowski ◽

R. R. Barnhart ◽

E. M. Campbell ◽

E. B. Hansen

Keyword(s):

Physical Properties ◽

Oxidative Degradation ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Gel Content ◽

Polymer Stability ◽

Heat Degradation ◽

Mooney Viscosity ◽

Styrene Butadiene ◽

Acid Coagulation

Abstract (1) Styrene-butadiene rubber (SBR) is very susceptible to oxidative degradation unless an effective stabilizing agent is incorporated in the polymer during manufacture. (2) Degradation of SBR appears as discoloration or resinification during drying of the polymer or during storage. Changes in the polymer may appear as variation in Mooney viscosity or as an increase in gel content. (3) Deterioration of inadequately stabilized SBR may also show up during processing operations when the polymer is subjected to heat—as in the Banbury or on a hot mill. (4) Deterioration of SBR polymer will appear as degraded physical properties in the cured vulcanizate. (5) The rubber goods manufacturer will benefit from the use of a really effective SBR stabilizer incorporated in the polymer during manufacture or by adding additional stabilizer to provide more protection against heat degradation in his operations. (6) Tris(nonylated aryl) phosphite exhibits unusual effectiveness as a stabilizer for SBR. (7) The presently widely used method of salt-acid coagulation of SBR polymer leaves room for improvement as far as polymer stability is concerned. (8) The more effective SBR stabilizers exhibit benefits in the aging of SBR vulcanizates.

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Carbon Nanotubes in Tyre Rubbers. Part 2: A Study of the Effect of Nanotubes on the Properties of Carbon-black-filled Tread Rubbers

International Polymer Science and Technology ◽

10.1177/0307174x1704400304 ◽

2017 ◽

Vol 44 (3) ◽

pp. 19-24

Author(s):

A.R. Mukhtarov ◽

A.M. Mokhnatkin ◽

V.P. Dorozhkin ◽

E.G. Mokhnatkina ◽

V.E. Muradyan ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Black ◽

Stearic Acid ◽

Dynamic Properties ◽

Single Layer ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Cohesion Strength ◽

Mooney Viscosity ◽

Styrene Butadiene

The processing and mechanical properties of green and vulcanised tread rubbers based on a blend of two types of styrene butadiene rubber filled with carbon black and containing single-layer carbon nanotubes (SCNTs) were studied. Three types of rubber mix were prepared: one containing untreated SCNTs and stearic acid, and two with SCNTs treated by different methods. The properties of these composites were compared. In all cases, the introduction of SCNTs leads to an increase in the cohesion strength of green rubber mixes, to an improvement in their vulcanisation properties, and to an increase in the Mooney viscosity, and also to an improvement in the dynamic properties of the vulcanisates, and here the Payne effect increases. There is also an improvement in the wear resistance, especially in the case of introducing untreated SCNTs and stearic acid which ensures the presence of –COOH groups.

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