Online Characterization of the Effect of Mixing Parameters on Carbon Black Dispersion in Rubber Compounds Using Electrical Conductivity

2004 ◽  
Vol 77 (1) ◽  
pp. 147-160 ◽  
Author(s):  
H. H. Le ◽  
S. Ilisch ◽  
B. Jakob ◽  
H.-J. Radusch
Keyword(s):  
Electrical Conductivity ◽  
Carbon Black ◽  
Mixing Parameters ◽  
Rubber Compounds ◽  
Mixing Regime ◽  
Internal Mixer ◽  
Optimal Mixing ◽  
Insight Into ◽  
Carbon Black Dispersion

Abstract The influences of mixing parameters on the carbon black dispersion can be characterized using the electrical conductivity online measured from internal mixer. As a measure for monitoring the development of carbon black dispersion, a normalized conductivity with regard to the conductivity measured at the BIT (black incorporation time) has been suggested. It is observed that in spite of different mixing parameters, the mixtures possessing the same normalized conductivity factor K/KBIT deliver the same carbon black dispersion and the same mechanical properties. Based on normalized conductivity, a deeper insight into the mixing kinetics can be provided to find an optimal mixing regime.

Online Method for Characterization of the Homogeneity of Rubber Compounds Filled with Non-Conductive Carbon Black

2006 ◽  
Vol 79 (4) ◽  
pp. 610-620 ◽  
Author(s):  
H. H. Le ◽  
M. Tiwari ◽  
S. Ilisch ◽  
H-J. Radusch
Keyword(s):  
Carbon Black ◽  
Electrical Conductance ◽  
Rubber Compound ◽  
Mixture Ratio ◽  
Dispersion Process ◽  
Filled Rubber ◽  
Rubber Compounds ◽  
Conductance Method ◽  
Internal Mixer

Abstract In the present work, the effect of carbon black (CB) type on the electrical conductance of CB filled rubber compounds measured online in the internal mixer and the corresponding CB dispersion were investigated. The CB dispersion is strongly affected by the specific surface area and structure of CB which can be directly monitored by use of the online electrical conductance method. The effect of CB mixture ratio of a high conductive CB and a non-conductive one on the online electrical conductance was investigated for CB filled rubber compounds. By addition of a small amount of a high-conductive CB type into a non-conductive CB filled rubber compound, a characteristic online conductance - time characteristic is observed that is a result of the formation of a joint network of the two CB types. It could be shown, that such a characteristic is suitable to monitor the dispersion process of the non-conductive CB in the rubber compound.

Characterization of Snap-On Calf Nipple Product and Development of its Compound Formulation Based on Natural Rubber

2017 ◽  
Vol 744 ◽  
pp. 282-287
Author(s):  
Sarawut Prasertsri ◽  
Sansanee Srichan
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Calcium Carbonate ◽  
Carbon Black ◽  
Natural Rubber ◽  
Soxhlet Extraction ◽  
Rubber Compound ◽  
Rubber Compounds ◽  
Rubber Component

This research aimed to develop the formulation of natural rubber filled with carbon black, silica and calcium carbonate for rubber calf nipple application. The reverse engineering was performed on the calf nipple product to analyze the rubber type and component by using Soxhlet extraction, thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) techniques. Furthermore, mechanical properties were examined to act as benchmark for the rubber compound design. The results showed that rubber component in the nipple product was natural rubber, whereas two filler types revealed as carbon black and calcium carbonate with 10 and 35 of the total weight. In addition, rubber nipple showed the hardness of 46±1 Shore A and tensile strength of 5.3±0.60 MPa. From the investigation of the properties of developed rubber compounds in this work, it was found that the mechanical properties depended on type and content of filler. The required mechanical properties of vulcanizates were achieved at 20 phr of carbon black (N330), 20 phr of silica and 120 phr of calcium carbonate.

THERMOREVERSIBLE CROSS-LINKING OF RUBBER COMPOUNDS: FROM PROOF-OF-CONCEPT TOWARD AN INDUSTRIAL PROCESS

2018 ◽  
Vol 91 (2) ◽  
pp. 492-508 ◽  
Author(s):  
L. M. Polgar ◽  
J. Keizer ◽  
R. Blom ◽  
B. Niemeijer ◽  
T. de With ◽  
...  
Keyword(s):  
Carbon Black ◽  
Material Properties ◽  
Industrial Process ◽  
Mineral Oil ◽  
Diels Alder ◽  
Cross Linking ◽  
Proof Of Concept ◽  
Rubber Compounds ◽  
Internal Mixer ◽  
Batch Mixer

ABSTRACT It is demonstrated that the concept of thermoreversible cross-linking of functionalized maleic anhydride grafted ethylene–propylene (EPM-g-MA) rubber using Diels–Alder chemistry is limited neither to laboratory scale using a solvent route nor to gum rubber. The use of an internal mixer is the first step toward an industrial process, since it greatly reduces the processing time and allows for a solventless process for the furan-functionalization and subsequent bismaleimide cross-linking of EPM rubber. Practical rubber compounds were prepared by mixing thermoreversibly cross-linked EPM with carbon black and mineral oil in the same batch mixer. This resulted in reinforcement of the rubber without affecting the thermoreversible character of the cross-linking. The pendant furan groups of the (non)cross-linked EPM-g-furan interact with the carbon black filler. Finally, crystalline EPM rubber compounds were prepared, which show excellent material properties and property retention over multiple reprocessing cycles.

Contributions of Elastomer Behavior to Mechanisms of Carbon Black Dispersion

1984 ◽  
Vol 57 (1) ◽  
pp. 153-167 ◽  
Author(s):  
N. Nakajima ◽  
E. R. Harrell
Keyword(s):  
Carbon Black ◽  
Effective Means ◽  
High Stress ◽  
Flow State ◽  
Breakdown Mechanism ◽  
Roll Mill ◽  
Highly Stretchable ◽  
Internal Mixer ◽  
Region Ii ◽  
Carbon Black Dispersion

Abstract In order to achieve good mixing of elastomer and carbon black, the elastomer domains must be reduced in size, that is, the elastomer must be broken into smaller pieces. If this is the only requirement, Region I of the Tokita-White scheme may be most preferred, because the elastomer easily breaks up at this state. However, it is too stiff for compaction of the compound; that is, the elastomer is too stiff to conform to the complex topology of carbon black. If the compaction is the only requirement. Region IV is most preferred, because the material is in the melt-flow state. In reality, Region II, the rubbery, highly stretchable state gives the best result. It appears that the use of Region II is a compromise. However, there is a more important reason for the preference of Region II, that is, the effectiveness of this region for the breakdown of carbon black agglomerates. The breakdown mechanism involves elastomer as a medium for the transfer of force. The effectiveness of the elastomer medium depends on its ability to stretch with the development and maintenance of a high stress. The former may be characterized by the failure envelop and the latter by the stress relaxation experiments. In roll mill as well as internal mixer processing, the folding of compound and the subsequent stretching of it, e.g., lamination mechanism, are the effective means for carbon black dispersion. It is postulated that the lamination mechanism generates localized high shear fields, which force carbon black agglomerates to rotate in the high modulus medium; this results in peeling of the aggregates from the outer shells of the agglomerates.

Online Electrical Conductivity as a Measure to Characterize the Carbon Black Dispersion in Oil Containing Rubber Compounds with a Different Polarity of Rubber

2004 ◽  
Vol 77 (5) ◽  
pp. 815-829 ◽  
Author(s):  
H. H. Le ◽  
I. Prodanova ◽  
S. Ilisch ◽  
H.-J. Radusch
Keyword(s):  
Electrical Conductivity ◽  
Carbon Black ◽  
Conductivity Measurement ◽  
Infiltration Rate ◽  
Rubber Matrix ◽  
Electrical Conductivity Measurement ◽  
Infiltration Process ◽  
The Matrix ◽  
Polar Oil ◽  
Carbon Black Dispersion

Abstract The influence of viscosity, polarity of the rubber matrix and the types and contents of extender oil on the carbon black dispersion has been characterized using the online electrical conductivity measurement. A corresponding change of the online conductivity with the rubber infiltration and extent of carbon black dispersion has been observed. The infiltration rate increases with increasing polarity and decreasing viscosity of the rubber matrix, whereby the matrix polarity shows a stronger effect than the viscosity. The oil addition accelerates the infiltration process. This is caused by the reduction of the matrix viscosity and the intensification of the filler-matrix interaction. Oil addition affects the carbon black dispersion in non-polar rubber much more than in polar rubber. Furthermore, in non-polar rubber, polar oil shows a stronger effect than non-polar oil.

scholarly journals Thermomechanical Characterization of Carbon Black Reinforced Rubbers During Rapid Adiabatic Straining

2021 ◽  
Vol 8 ◽  
Author(s):  
William Amoako Kyei-Manu ◽  
Lewis B. Tunnicliffe ◽  
Jan Plagge ◽  
Charles R. Herd ◽  
Keizo Akutagawa ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Morphological Properties ◽  
Amplification Factors ◽  
Mechanical Hysteresis ◽  
Rubber Compounds ◽  
Irreversible Effects ◽  
Styrene Butadiene ◽  
Extension Analysis

The thermo-mechanical properties of carbon black reinforced natural and styrene butadiene rubbers are investigated under rapid adiabatic conditions. Eleven carbon black grades with varying surface area and structure properties at 40 parts per hundred (phr) loading are studied and the unreinforced equivalents are included for reference. The results show a strong correlation of the modulus, mechanical hysteresis, temperature rise and calculated crystallinity of the rubbers measured in tensile extension with strain amplification factors. This highlights the influence of matrix overstraining on microstructural deformations of the rubber upon extension. The strain amplification factors are calculated via the Guth-Gold equation directly from carbon black type and loading, allowing a correlation of the fundamental morphological properties of carbon black with thermal and mechanical properties of rubbers upon extension. Analysis of the thermal measurements of the rubber compounds upon extension and retraction and contrasting between crystallizing and non-crystallizing rubbers reveals that a substantial irreversible heat generation is present upon extension of the rubber compounds. These irreversible effects most likely originate from microstructural damage mechanisms which have been proposed to account for the Mullins Effect in particle reinforced rubbers.

Some Initial Trials and Applications of the DFCS Test for Carbon Black Dispersion

1997 ◽  
Vol 70 (1) ◽  
pp. 38-49
Author(s):  
G. A. W. Murray ◽  
B. H. R. Ng ◽  
M. R. Vaseghi Jahromi ◽  
D. W. Southwart
Keyword(s):  
Standard Deviation ◽  
Carbon Black ◽  
Normal Distribution ◽  
Quantitative Method ◽  
Scattered Light ◽  
Dark Field ◽  
Test Results ◽  
Rubber Compounds ◽  
Cut Surface ◽  
Carbon Black Dispersion

Abstract The Dark Field Cut Surface (DFCS) test is a quantitative method for determining the state of dispersion of carbon black in rubber compounds. The method has been described fully in another paper. Here are reported some of the first applications of the test and some trials that were carried out specifically to investigate and develop the DFCS test. The test is demonstrated to follow accurately the progress of dispersion of carbon black in milled or mixed compounds of NR and SBR. Some tests have been carried out using large batches of test results and these have demonstrated a good fit with a normal distribution. By this means, some recommendations have been derived for suitable sampling rates. The relative merits of the standard deviation and the average for characterizing dispersion have been highlighted. A further way of presenting the results as distribution curves has been demonstrated. A check has been performed to demonstrate that mastication of rubber has little or no influence on the DFCS test results. The DFCS test has been used to give an interesting (provisional) insight to the best ways to operate a rubber mixer. To date, the measured patterns of scattered light show a promising correlation with the anticipated dispersion of carbon black in the specimens tested.

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