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

G. A. W. Murray; B. H. R. Ng; M. R. Vaseghi Jahromi; D. W. Southwart

doi:10.5254/1.3538417

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

Rubber Chemistry and Technology ◽

10.5254/1.3538417 ◽

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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The Dark Field Cut Surface (DFCS) Test for Estimating the Dispersion of Carbon Black in Rubber Compounds

Rubber Chemistry and Technology ◽

10.5254/1.3538418 ◽

1997 ◽

Vol 70 (1) ◽

pp. 50-59 ◽

Cited By ~ 3

Author(s):

G. A. W. Murray ◽

D. W. Southwart ◽

P. K. Freakley

Keyword(s):

Carbon Black ◽

Numerical Estimate ◽

Dark Field ◽

Field Of View ◽

High Magnification ◽

Ability To Work ◽

Rubber Compounds ◽

Dark Field Illumination ◽

Cut Surface ◽

Initial Results

Abstract A test for estimating the dispersion of carbon black in rubber compounds is described. It works by examining the freshly cut surface of a specimen at low magnification in dark field illumination. Roughness of the surface related to the presence of carbon black causes increased reflection under dark field illumination. The illumination of each field of view is examined as 100 subdivisions and the relative values of these readings give a numerical estimate of the dispersion. Details of how this is done and the corrections applied to the results are described. A second paper reports some initial results obtained with the test. The test works well for certain elastomers, notably NR and SBR. The biggest advantage of the test is its ability to work rapidly and cheaply on small zones at relatively high magnification. This opens up the possibility of detailed studies of macroscopic variations in dispersion, done in reasonable times and at reasonable costs.

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Carbon Black Dispersion Measurement in Rubber Vulcanizates via Interferometric Microscopy

Rubber Chemistry and Technology ◽

10.5254/1.3547845 ◽

2004 ◽

Vol 77 (4) ◽

pp. 691-710 ◽

Cited By ~ 4

Author(s):

Archie P. Smith ◽

Toni L. Aybar ◽

Ricky W. Magee ◽

Charles R. Herd

Keyword(s):

Carbon Black ◽

Three Dimensional ◽

Dispersion Index ◽

Complete Understanding ◽

Additional Information ◽

Rubber Compounds ◽

Varying Dispersion ◽

Light Beams ◽

Cut Surface ◽

Carbon Black Dispersion

Abstract A new method for characterizing the carbon black dispersion in rubber compounds is introduced. This technique is based on interferometric microscopy (IFM) and utilizes the interference fringes between in-phase light beams reflected from the rubber sample and a smooth reference surface to measure the three-dimensional surface topography. The peaks and valleys present on the fresh-cut surface are representative of the carbon black agglomerates and are used to characterize the dispersion. A series of samples with different base rubbers and varying dispersion levels were created and characterized by both light microscopy and IFM. These results were used to generate a universal dispersion index based on the IFM data that correlates well with the LM dispersion index values. In addition, three-dimensional peak statistics were obtained from the IFM data and used to provide additional information about the carbon black agglomerate distribution. This data can be used for a more complete understanding of the compound behavior as a function of the carbon black dispersion and agglomerate distribution.

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

Rubber Chemistry and Technology ◽

10.5254/1.3538414 ◽

1997 ◽

Vol 70 (1) ◽

pp. 15-24 ◽

Cited By ~ 11

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.

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

Rubber Chemistry and Technology ◽

10.5254/1.3547808 ◽

2004 ◽

Vol 77 (1) ◽

pp. 147-160 ◽

Cited By ~ 15

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.

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An Investigation of the Effect of Taurit Filling of Rubber Mixes for the Coating of Radial Lorry Tyre Breakers

International Polymer Science and Technology ◽

10.1177/0307174x1704401105 ◽

2017 ◽

Vol 44 (11) ◽

pp. 21-24

Author(s):

R.R. Mindubaev ◽

A.M. Mokhnatkin ◽

V.P. Dorozhkin ◽

E.G. Mokhnatkina

Keyword(s):

Carbon Black ◽

Particle Distribution ◽

Elastic Recovery ◽

Dynamic Strength ◽

Carbon Black Particle ◽

Test Results ◽

Rubber Compound ◽

Rubber Compounds ◽

Black Particle ◽

Internal Mixer

The results of investigating the effect of the shungite analogue Taurit (grade TSD) on the properties (measured on an RPA 2000 instrument) of a breaker rubber mix and of a rubber compound based on synthetic isoprene rubber SKI-3 are set out. Different methods of introducing Taurit have been tested: 10 parts into the rubber at the stage of its production; 10 parts into the standard rubber mix at the first stage of mixing; 10 parts into the rubber subjected to preliminary mechanical plasticisation in a laboratory internal mixer at a temperature of 100°C. The introduction of Taurit into the rubber in small quantities in order to reduce the proportion of rubber constituent in the rubber mix has also been tested. The test results have been compared with results for standard rubber mixes and rubber compounds. When Taurit is introduced into rubber at the stage of its production, the cohesive strength of the rubber mix and the rate of its vulcanisation and also the dynamic modulus components G′ and G″ are increased. When Taurit is introduced into plasticised rubber, again G′ and G″ are increased, there is an increase in plasticity, and the elastic recovery of the rubber mix is reduced. The breaker rubber compound from this mix has the best adhesion to metal cord and the highest dynamic strength. Data on the Payne effect indicate a better carbon black particle distribution when Taurit is introduced into the rubber at the stage of its production. Reduction in the proportion of rubber constituent in the rubber mix leads to a deterioration in the carbon black particle distribution.

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The Mechanism of Carbon Black Dispersion in Rubber Compounds Loaded at Practical Level

NIPPON GOMU KYOKAISHI ◽

10.2324/gomu.83.318 ◽

2010 ◽

Vol 83 (10) ◽

pp. 318-323 ◽

Cited By ~ 2

Author(s):

Asahiro AHAGON ◽

Kazuo MIYASAKA

Keyword(s):

Carbon Black ◽

Rubber Compounds ◽

Practical Level ◽

Carbon Black Dispersion

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A Preparation of High Resolution Standards for Electron Microscopy. Part II

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064852 ◽

1971 ◽

Vol 29 ◽

pp. 160-161

Author(s):

Akira Tanaka ◽

David F. Harling

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Carbon Black ◽

Single Crystal ◽

Dark Field ◽

Graphitized Carbon Black ◽

Graphitized Carbon ◽

Dark Field Imaging ◽

Crystal Films ◽

Micro Holes

In the previous paper, the author reported on a technique for preparing vapor-deposited single crystal films as high resolution standards for electron microscopy. The present paper is intended to describe the preparation of several high resolution standards for dark field microscopy and also to mention some results obtained from these studies. Three preparations were used initially: 1.) Graphitized carbon black, 2.) Epitaxially grown particles of different metals prepared by vapor deposition, and 3.) Particles grown epitaxially on the edge of micro-holes formed in a gold single crystal film.The authors successfully obtained dark field micrographs demonstrating the 3.4Å lattice spacing of graphitized carbon black and the Au single crystal (111) lattice of 2.35Å. The latter spacing is especially suitable for dark field imaging because of its preparation, as in 3.), above. After the deposited film of Au (001) orientation is prepared at 400°C the substrate temperature is raised, resulting in the formation of many square micro-holes caused by partial evaporation of the Au film.

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