scholarly journals Effects of mixing temperature on the extrusion rheological behaviors of rubber-based compounds

RSC Advances ◽  
2021 ◽  
Vol 11 (56) ◽  
pp. 35703-35710
Author(s):  
Zhongjin Du ◽  
Yu Du ◽  
Yankun Gong ◽  
Guizhi Liu ◽  
Zhuo Li ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Carbon Black ◽  
Weight Change ◽  
Die Swell ◽  
Mixing Process ◽  
Rheological Behaviors ◽  
Rubber Compounds

The carbon black dispersity and rubber molecular weight change during the mixing process were the important factors determining the die swell behavior of the rubber compounds.

DERIVATIZATION OF SOYBEAN OIL TO ENHANCE PERFORMANCE AS A PROCESSING OIL IN SBR-BASED RUBBER COMPOUNDS

2020 ◽  
Author(s):  
Olena Shafranska ◽  
Andrey Chernykh ◽  
Bret J. Chisholm ◽  
Ihor Tarnavchyk ◽  
Dean C. Webster
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Carbon Black ◽  
Soybean Oil ◽  
Rolling Resistance ◽  
Degree Of Unsaturation ◽  
Rubber Compounds ◽  
Direct Replacement ◽  
Crosslink Densities

ABSTRACT Although soybean oil (SBO) has been used as a bio-based processing oil (PO) for rubber compounds, direct replacement of a conventional petroleum-based PO with SBO often results in a reduction of some important properties. As a result, it was of interest to investigate two higher molecular weight SBO-derived materials as POs, namely, sucrose octasoyate (SS) and poly(2-vinyloxyethyl)soyate (P2VOES). When these compounds were used in carbon black (CB)-filled SBR, mechanical properties were significantly improved. This result was mainly attributed to higher crosslink densities resulting from their higher degree of unsaturation per molecule as compared with SBO. Higher unsaturation per molecule increases the probability that the PO will be incorporated into the crosslinked network as elastically effective crosslinks as opposed to dangling chain ends. With regard to tire tread performance, both SS and P2VOES-based vulcanizates showed a lower predicted rolling resistance than the SBO-based control, and the P2VOES vulcanizate showed a better balance between rolling resistance and wet traction. Vulcanizates derived from SS and P2VOES showed a small tangent delta peak between −13 and 35 °C that might be associated with relatively highly crosslinked domains rich in SS or P2VOES.

Relationship between Molecular Structure and Mixing Mechanism

1987 ◽  
Vol 60 (1) ◽  
pp. 14-24 ◽  
Author(s):  
S. Shiga
Keyword(s):  
Molecular Structure ◽  
Molecular Weight ◽  
Carbon Black ◽  
Mixing Time ◽  
Molecular Size ◽  
Rubber Compounds ◽  
Bound Rubber ◽  
Strong Linear Correlation ◽  
Black Surface ◽  
The Relationship

Abstract The relationship between the molecular weight, the bound rubber, and the PI value was studied for EPR, of which the molecular structure was measured with GPC-LALLS. A strong linear correlation is found between the bound rubber and the PI value. The Meissner theorem, modified to express a severer dependence of the bound rubber on the molecular weight than the original theorem expects and the use of a molecular size instead of the molecular weight, can explain the relationship between the molecular weight and the bound rubber, accordingly the PI value. They indicate not only the dependence of mixing processability on polymer adsorption, but also strongly suggest the mechanism of carbon black dispersion that aggregates are scraped out from the surface of agglomerates as illustrated by the onion model. A pulsed NMR was used to measure the spin-spin relaxation time T2 of EPR in rubber compounds of different mixing time to study the rubber phase structure and its time change. It can be imagined from the T2-time curves that till tmin, polymer molecules are rapidly bound on the carbon black surface to become thick gradually, while adsorbed segments per a molecule increase with time. After tmin, gradual rearrangement of molecules on the surface and the biphasic structure of the bound rubber may proceed. The whole thickness of the bound rubber increases gradually even after tmin. The resistance against the dispersion of carbon black seems to be strengthened with mixing time.

Effect of Processing Additives on Carbon Black Dispersion and Grip Property of High-Performance Tire Tread Compound

1997 ◽  
Vol 70 (1) ◽  
pp. 15-24 ◽  
Author(s):  
H. Takino ◽  
S. Iwama ◽  
Y. Yamada ◽  
S. Kohjiya
Keyword(s):  
Carbon Black ◽  
Viscoelastic Properties ◽  
High Performance ◽  
Mixing Process ◽  
Remarkable Effect ◽  
Rubber Compounds ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Power Curves ◽  
Carbon Black Dispersion

Abstract Rubber and carbon black compounds show complex behaviors in their mixing process due to their complicated microcomposite structure. Therefore, establishing a clear relationship between the mixing state of the rubber compound and the physical properties of its cured rubber has still remained to be solved in spite of formidable efforts by many rubber technologists. This paper investigated the influence of a processing additive on the carbon black incorporation and its dispersion behavior by inspecting Banbury power curves. From this investigation, we considered that good wettability toward the carbon black surface was necessary for processing additives in order to improve carbon black dispersion. The function of the processing additive was thought to enhance the surface lubrication of carbon black for disagglomeration in the early steps of mixing. The dry grip properties of a tire was estimated from the temperature dependence of dynamic viscoelastic properties of rubber compounds, with improved carbon black dispersion due to the processing additive; and it was confirmed by an actual tire running evaluation. Consequently, we found that tread compounds with improved carbon black dispersion had a remarkable effect on tire dry-grip properties at high temperatures.

Compound Processability and Molecular Weight Distribution of SBR

1976 ◽  
Vol 49 (2) ◽  
pp. 291-302 ◽  
Author(s):  
W. Mills ◽  
F. Giurco
Keyword(s):  
Molecular Weight ◽  
Carbon Black ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Mixing Time ◽  
Die Swell ◽  
Similar Information ◽  
Unit Work ◽  
Normal Production ◽  
Mooney Viscosity

Abstract Nonuniformities in the mixing and extrusion behavior of nominally standard grades of emulsion- and solution-polymerized oil-extended SBR are associated with variations in molecular weight distribution but are not reflected by Mooney viscosity. The variations in the samples studied were representative of normal production material. The solution-polymerized polymers characteristically exhibit wider variations in compound die swell and have generally more rapid dispersion of carbon black than comparable emulsion-polymerized polymers. This is true, regardless of whether BIT or t′ point is considered as a measure of carbon black dispersibility. Generally, increasing polydispersity increases compound die swell and retards the rate of carbon-black dispersion. Utilization of unit work instead of mixing time as a measure for torque rheometer processability gives similar information on carbon-black dispersibility. However, unit work is preferred because of the promise it holds for scaleup and interlaboratory correlation. Delta Mooney values, and to a lesser extent peak Mooney torque, provide a useful basis for predicting the mixing and extrusion behavior of oil-extended SBR. The torque rheometer t′ point recently proposed as an index for carbonblack dispersibility is also useful for predicting compound die swell.

scholarly journals Effect of Adding MoDTC on the Properties of Carbon Black Rubber and the Friction and Wear of Metal during Mixing Process

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1071
Author(s):  
Yiren Pan ◽  
Deshang Han ◽  
Lin Zhu ◽  
Meng Zhang ◽  
Huiguang Bian ◽  
...  
Keyword(s):  
Carbon Black ◽  
Friction And Wear ◽  
Mixing Process ◽  
Rubber Compounds ◽  
Metal Wear ◽  
Mixing Chamber ◽  
Long Time ◽  
Filler Dispersion ◽  
Rubber Product

The gap between the rotor and the mixer chamber wall is an important factor in determining filler dispersion in rubber compounds. The inner wall of a mixer will wear after working for a long time, which will cause poor filler dispersion and affect the quality of rubber products. In this study, MoDTC was added to carbon black as a kind of filler, and the effect on filler dispersion, the properties of the rubber product, and the friction and wear of rubber and metal in the mixing process were examined. Experimental data showed that after adding 3 phr of MoDTC, carbon black dispersion was greatly improved, the curing time was shortened, and the performance remained stable. It was also found that the Mo element of the compound with 3 phr MoDTC dispersed better than that of the other compounds. Most importantly, adding 3 phr of MoDTC greatly reduced the amount of wear on the metal during the mixing process. However, the opposite effect occurred when the MoDTC content was high. The method proposed in this study can not only improve filler dispersion in rubber but also reduce metal wear to prolong the service life of the mixing chamber when applied to an actual mixing process.

The Dependence of Processability on Molecular Weight Distribution of Elastomers

1973 ◽  
Vol 46 (5) ◽  
pp. 1166-1187 ◽  
Author(s):  
N. Tokita ◽  
I. Pliskin
Keyword(s):  
Molecular Weight ◽  
Carbon Black ◽  
Weight Distribution ◽  
Mixing Time ◽  
Die Swell ◽  
Quantitative Characterization ◽  
Failure Characteristics ◽  
Deformational Behavior ◽  
Filler Dispersion

Abstract After examining the mechanism of mixing of elastomer with filler by both internal mixers and open mills, the failure characteristics of an elastomer (extension to break and ratio of elasticity to plasticity) were found to be important properties affecting the filler wetting and dispersion rates. The failure characteristics have also been shown to depend on the polymer MWD, branching, and microstructure. A quantitative characterization of deformational behavior and failure of uncured material has been presented. Also, an attempt has been made to establish a link between the more basic properties of elastomers and processability, particularly the rate of filler dispersion in mixing. The variation of compound Mooney torque and die swell with mixing time can be explained theoretically by taking account of the occluded rubber trapped by the carbon black agglomerates. As filler dispersion increases, the amount of such occluded rubber decreases, Mooney torque decreases, and die swell increases as expected from the theory of rheology of composites.

Partial replacement of carbon black by nanoclay in butyl rubber compounds for tubeless tires

2017 ◽  
Vol 59 (11-12) ◽  
pp. 1054-1060 ◽  
Author(s):  
Mohan Kumar Harikrishna Kumar ◽  
Subramaniam Shankar ◽  
Rathanasamy Rajasekar ◽  
Pal Samir Kumar ◽  
Palaniappan Sathish Kumar
Keyword(s):  
Carbon Black ◽  
Butyl Rubber ◽  
Partial Replacement ◽  
Rubber Compounds

scholarly journals Insights into the Payne Effect of Carbon Black Filled Styrene-butadiene Rubber Compounds

2020 ◽  
Vol 39 (1) ◽  
pp. 81-90
Author(s):  
An Zhao ◽  
Xuan-Yu Shi ◽  
Shi-Hao Sun ◽  
Hai-Mo Zhang ◽  
Min Zuo ◽  
...  
Keyword(s):  
Carbon Black ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Payne Effect ◽  
Rubber Compounds ◽  
Styrene Butadiene
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