Carbon Black Treadwear Ratings from Laboratory Tests

1986 ◽  
Vol 59 (3) ◽  
pp. 497-511 ◽  
Author(s):  
E. M. Dannenberg
Keyword(s):  
Carbon Black ◽  
Laboratory Tests ◽  
Wear Performance ◽  
Carbon Blacks ◽  
Bound Rubber ◽  
Road Testing

Abstract It has been seen from the above survey that a few of the treadwear predictor correlations have the required accuracy to provide a satisfactory alternative to road testing of tires for the wear performance of carbon blacks, depending on requirements and circumstances. Correlations based on laboratory rubber testing of rubber mixes and tread compounds are to be preferred over those based solely on carbon black colloidal and morphological measurements. In the author's opinion, Cotten and Dannenberg's correlation of treadwear index with Angle Abrasion measurements of 30 phr compounds and heated bound rubber, and Westlinning and Wolff's correlation with rebound resilience, and the Monsanto Rheometer determination of αF are satisfactory in most instances for the prediction of the treadwear index behavior of carbon blacks.

A Method for Evaluation of Carbon Blacks and Correlation with Road Wear Ratings

1974 ◽  
Vol 2 (3) ◽  
pp. 211-228 ◽  
Author(s):  
G. R. Cotten ◽  
E. M. Dannenberg
Keyword(s):  
Carbon Black ◽  
Abrasion Resistance ◽  
Laboratory Tests ◽  
The Other ◽  
Rubber Content ◽  
Carbon Blacks ◽  
Heat Treated ◽  
Bound Rubber ◽  
Normal Production

Abstract Prediction of tread wear from laboratory tests can be a valuable guide in the development of improved carbon blacks and controlling the quality of normal production. We have developed two tests which give good correlation with actual road wear data on over 100 experimental blacks. One test involves running Akron angle abrasion on a compound with only 30 phr of carbon black where differences in abrasion resistance are magnified. The other test measures surface activity towards the polymer by determining bound rubber content of a heat-treated nonproductive mix. By using both tests together, tread wear ratings of blacks used in this study could be predicted almost as well as by a single, controlled, multisectional road test with five tires run for 8000–10,000 miles.

Effects of the Types of Rubber and Carbon Black on the Formation of Carbon-Rubber Gel

1959 ◽  
Vol 32 (4) ◽  
pp. 1185-1191
Author(s):  
Z. V. Chernykh ◽  
V. G. Epshtein
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Gel Formation ◽  
Active Carbons ◽  
Carbon Blacks ◽  
Bond Stability ◽  
Carbon Structures ◽  
Bound Rubber

Abstract 1. Carbon-rubber gels are formed in mixtures containing all the types of carbon black tested (channel, acetylene, nozzle, furnace, thermal) and not only active carbons. 2. The amount of carbon-rubber gel formed depends on the amount of carbon black added. With carbon blacks which readily form continuous carbon structures (channel, acetylene) the amounts of gel are greater than with nonstructural blacks, for the same amount of black added. 3. The amount of gel is greater in synthetic than in natural rubber mixtures. 4. More intense extraction conditions do not cause disappearance of the gel, but increase the amount of bound rubber and decrease the amount of carbon in the gel. 5. The carbon-rubber gels formed from structural carbons contain larger amounts of bound rubber. 6. It is suggested that bond stability between carbon black particles (characterized by the formation of a carbon black structure) is one of the basic causes of carbon-rubber gel formation.

Mixing of Carbon Black with Rubber I. Measurement of Dispersion Rate by Changes in Mixing Torque

1984 ◽  
Vol 57 (1) ◽  
pp. 118-133 ◽  
Author(s):  
George R. Cotten
Keyword(s):  
Carbon Black ◽  
Volume Fraction ◽  
Small Samples ◽  
Butadiene Rubber ◽  
Mixing Process ◽  
Carbon Blacks ◽  
Bound Rubber ◽  
Power Peak ◽  
Dispersive Mixing ◽  
Carbon Black Dispersion

Abstract Analysis of the torque data obtained for a large range of carbon blacks in an oil-extended butadiene rubber (CB-441) shows that the rate of decrease of torque (after the second power peak) follows first order kinetics. The rate of decrease represents the rate of reduction in effective filled volume fraction through dispersion of carbon black agglomerates, and thus, a reduction in the volume of rubber occluded between individual aggregates within the agglomerates. The assumption that the rate of torque reduction is proportional to the rate of carbon black dispersion was tested by examining the responses to various factors influencing the mixing process. In general, the conclusions reached from the analysis of torque data were in agreement with the common industrial experience and predictions based on the mathematical analysis of dispersive mixing. Tadmor's analysis of dispersive mixing predicts that the rate of agglomerate rupture depends on the number of particle-particle contacts and thus is related to the size of individual aggregates, but is independent of agglomerate size. Thus, it is in agreement with the present findings that the rate of dispersive mixing increases with decreasing surface area and increasing structure of aggregates. Increasing polymer-filler interaction gives rise to a faster rate of dispersive mixing, possibly by increasing the effective radii of aggregates through bound rubber formation. Increasing the batch temperature increases the rate of dispersive mixing due to reduced cohesion between the aggregates and a more favorable balance between cohesive and shearing forces. Increasing carbon black loading increases the rate of dispersive mixing by increasing the viscosity and, thus, shearing forces generated during the mixing process. The technique developed in this work may provide a better means for measuring dispersibility of carbon blacks, since other available methods suffer certain disadvantages. For instance, the resistivity measurements are not only dependent on carbon black dispersion, but also on the chemical nature of its surface, while microscopic methods depend on the examination of very small samples that may not be representative of the whole batch.

Formation of Bound Rubber of GR-S Type Polymers with Carbon Blacks

1952 ◽  
Vol 25 (3) ◽  
pp. 500-516 ◽  
Author(s):  
June Duke ◽  
W. K. Taft ◽  
I. M. Kolthoff
Keyword(s):  
Molecular Weight ◽  
Carbon Black ◽  
High Molecular Weight ◽  
Lower Molecular Weight ◽  
Carbon Blacks ◽  
Bound Rubber ◽  
Temperature Levels ◽  
Black Other ◽  
Lower Carbon

Abstract The bound rubber-black complex formed by milling various GR-S polymers and carbon blacks at several temperature levels was studied. The amount of bound polymer increased with greater loadings of black, but per unit of carbon black, it decreased at the higher black loadings. The temperature of mixing likewise has a large effect—at lower carbon black loadings, higher temperatures increase the amount of binding; the effect ia minimized as the loading is increased until at high loadings (100 to 125 parts of black per 100 parts of rubber) this effect is eliminated. By fractionation of the sol portion, it has been shown that polymer of progressively lower molecular weight is bound as the black loading is increased. Polymer of high molecular weight does not replace bound polymer of lower molecular weight; the polymer of higher molecular weight is preferentially bound during mill mixing. Although more polymer appears to be bound as the conversion is increased from 50 to 72 per cent at a loading of 50 parts of black, other factors besides conversion may be determinative. No differences in relationship were found for polymers made at 122° or 41° F.

Determination of Total Moisture in Carbon Blacks

1930 ◽  
Vol 3 (2) ◽  
pp. 340-341
Author(s):  
G. M. Carson
Keyword(s):  
Carbon Black ◽  
Calcium Chloride ◽  
Room Temperature ◽  
Constant Weight ◽  
Carbon Blacks ◽  
Method Of Determination ◽  
Air Condenser ◽  
Capillary Type ◽  
Time Required

Abstract IN THE course of an extended research on various grades of carbon black, determinations of total moisture were made by an adaptation of an old method. The method used was similar to one described by Allen and Jacobs (1) for measuring water in tar. The chief difference in the present method is that small amounts of moisture in carbon blacks must be weighed, whereas the larger amounts in tar could be measured. The difficulties in weighing the evolved moisture are described in the ensuing method of determination. Five grams of carbon black were placed in a 500-cc. round-bottom flask with 25 to 35 cc. of dry xylene and 200 cc. of dry mineral oil. A short air condenser led to the bottom of a 25-cc. distilling flask, which in turn was connected to two or more calcium chloride tubes. The flask containing the sample was heated to 150-175° C. in an oil bath, a stream of dry nitrogen being passed through the apparatus. The water and xylene were distilled into the small distilling flask and thence, by warming in a water bath, into the calcium chloride tubes, the current of nitrogen being continued. It required but a few minutes to remove the water from the xylene, indicated by the disappearance of cloudiness, and the calcium chloride tubes were then connected directly to the nitrogen line and the gas was passed through until the tubes reached constant weight. ylene is not adsorbed by calcium chloride and nitrogen does not remove water from it at room temperature during the time required for the experiment. The increase in weight of the calcium chloride tubes is the amount of water in the sample of carbon black. The amount of water thus determined is considerably higher than the 105° C. oven loss in 5 hours, and indicates that most of the moisture is of the “bound” or “capillary” type.

New Studies on the Surface Properties of Carbon Blacks

1990 ◽  
Vol 63 (5) ◽  
pp. 747-778 ◽  
Author(s):  
J. A. Ayala ◽  
W. M. Hess ◽  
A. O. Dotson ◽  
G. A. Joyce
Keyword(s):  
Carbon Black ◽  
Hydrogen Content ◽  
Surface Reactivity ◽  
Moisture Adsorption ◽  
Carbon Blacks ◽  
Surface Sites ◽  
Bound Rubber ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Polymer Interaction

Abstract A series of carbon blacks of widely varying morphology and microstructure were analyzed for surface compositional properties employing SIMS, XPS/ESCA, and GC-MS. These studies were supported by bulk analyses for hydrogen and oxygen content. Surface reactivity was assessed by means of inverse gas chromatography, moisture adsorption, and oxidation in an oxygen plasma. To directly assess carbon-black-polymer interaction, the carbon blacks were evaluated in SBR and IIR compounds for stress-strain and dynamic properties as well as bound rubber. The major findings of these studies are: 1. The combined results of hydrogen content, SIMS, and pyrolysis-GC-MS suggest a complex hydrogen functionality at the carbon-black surface, which governs the level of interaction with elastomers. 2. SIMS analyses have shown that the hydrogen functionality at the carbon-black surface is preserved after an 1173 K heat treatment in an inert atmosphere. 3. Gas-solid chromatography results indicate that this technique may be very useful to determine the degree of heterogeneity of a carbon-black surface. It also provides a tool to characterize the nature of the surface sites which are responsible for such a heterogeneity. 4. Moisture-adsorption rates provides a means to explore the reactivity of carbon-black-surface sites. Initial rates of adsorption can be well explained by a second-order-rate mechanism. 5. Bound-rubber development (SBR) and oxygen content per square meter of carbon-black-surface area were directly proportional to the hydrogen content of the black. The hydrogen content is considered to be the primary compositional factor relating to carbon-black-surface activity, while bound rubber and oxygen levels are specific measures of surface reactivity. 6. The slope of the stress-strain curves (or the modulus value) in the λ=1 to 3 region divided by the black networking factor, η (E′ at 2% ptp ÷ at 25% ptp), is sensitive to changes in black-polymer interaction. This ratio (σ/η or M/η) shows an excellent correlation with black hydrogen content and bound rubber (SBR). 7. The σ/η values for SBR and IIR are highly correlated, although the values for SBR are two to three times higher, and there was no measurable bound rubber for any of the IIR compounds. 8. The σ/η values for IIR (λ=2−3) and the oxygen/m2 values were found to be the best discriminators for black-polymer interaction in explaining within-grade treadwear variations in SBR/BR multisection radial-passenger treads.

AFM Study of Rubber Compounds

2005 ◽  
Vol 78 (1) ◽  
pp. 17-27 ◽  
Author(s):  
C. C. Wang ◽  
J. B. Donnet ◽  
T. K. Wang ◽  
M. Pontier-Johnson ◽  
F. Welsh
Keyword(s):  
Atomic Force Microscopy ◽  
Carbon Black ◽  
Surface Morphology ◽  
Force Microscopy ◽  
Carbon Blacks ◽  
Atomic Force ◽  
Rubber Compounds ◽  
Road Testing

Abstract A series of rubber compounds filled with carbon blacks and silica has been studied by atomic force microscopy (AFM). The microdispersion of carbon black aggregates in rubber compounds can be clearly observed. The surface morphology of worn treads after road testing studied by AFM is also reported.

The Application of Thermogravimetry (TG) to the Characterization and Quantitative Determination of Carbon Blacks

1982 ◽  
Vol 55 (2) ◽  
pp. 382-390 ◽  
Author(s):  
E. L. Charsley ◽  
J. G. Dunn
Keyword(s):  
Carbon Black ◽  
Accurate Method ◽  
Maximum Temperature ◽  
Free Form ◽  
Carbon Black Content ◽  
Carbon Blacks ◽  
Quality Control Check ◽  
Routine Quality Control ◽  
Definite Correlation

Abstract (1) The experimental variables which are found to affect significantly the measured T15 value for compounded carbon blacks are: (a) the maximum temperature achieved during the pyrolysis step and (b) the flow rate of air and the heating rate used during the oxidation step. (2) There is a definite correlation between the T15 value and the surface area of a carbon black, both in its free form and when compounded in a rubber. The T15 value is dependent on the cure method of the rubber and has also recently been reported to depend on the manufacturing source of the carbon black. This technique, therefore, cannot be recommended as suitable for the identification of a carbon black type in an unknown formulation. It can be used, however, as a routine quality control check on batch rubbers. (3) Thermogravimetry can be used as a rapid and accurate method for the determination of the carbon black content of rubbers, at levels as far apart as 0.1% and 30%.

Carbon-Black-Elastomer Interaction

1991 ◽  
Vol 64 (1) ◽  
pp. 19-39 ◽  
Author(s):  
J. A. Ayala ◽  
W. M. Hess ◽  
F. D. Kistler ◽  
G. A. Joyce
Keyword(s):  
Carbon Black ◽  
Surface Activity ◽  
Chemical Reactivity ◽  
Surface Reactivity ◽  
Moisture Adsorption ◽  
Carbon Blacks ◽  
Bound Rubber ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Polymer Interaction

Abstract A number of different techniques were applied to measure carbon-black-surface reactivity and the level of black-polymer interaction in four different elastomer systems (SBR, IIR, NR, and NBR) representing differences in unsaturation, crystallinity and polarity. Known within-grade surface activity variations were based on partial graphitization of an N121-type carbon black. The surface activity of different black grades was studied as a function of variations in both surface area and DBPA. Direct measurements of carbon-black-surface reactivity were based on hydrogen analysis, SIMS, IGC, and moisture adsorption. In-rubber measurements included bound rubber, SIMS of cut surfaces, and an interaction parameter, σ/η, which is derived from the slope (σ) of the stress-strain curve at low elongations, and (η), the ratio of dynamic modulus (E′) at 1% and 25% DSA. The following trends were observed: 1. The σ/η values provided a good measure of black-polymer interaction in all four polymer systems for either the within-grade or across-grade comparisons. 2. Higher σ/η values were indicated for SBR and NBR, followed by NR and IIR in that order. 3. SBR indicated the greatest sensitivity for bound-rubber measurements in terms of distinguishing within-grade variations in black-polymer interaction, followed by IIR, NR, and NBR in that order. 4. Positive SIMS on dry carbon black indicates the presence of complex hydrocarbon structures suitable for chemical reactivity at the carbon-black surface. 5. SIMS analyses on the dry carbon blacks exhibited intensity variations in the negative hydrocarbon fragments which were in line with the within-grade variations in hydrogen content. 6. SIMS analyses on the cut-rubber compound surfaces showed overall variations in intensity which were proportional to the range and level of the bound-rubber measurements. The most meaningful variations were recorded for SBR and IIR. 7. Heats of adsorption derived from IGC measurements with different adsorbates showed an excellent correlation with black-polymer interaction for the within-grade studies. Measurements across grades did not correlate as well with the in-rubber measurements, but the best results were obtained using styrene as the adsorbate. 8. The within-grade moisture adsorption measurements showed excellent agreement with IGC and the other techniques for the N121 series of heat-treated carbon blacks.

Profil Penyakit Malaria Di Rumah Sakit Islam Siti Rahmah Padang Tahun 2018

2020 ◽  
Vol 2 (2) ◽  
pp. 08-15
Author(s):  
Rahma Triyana ◽  
Salmi Salmi
Keyword(s):  
Observational Study ◽  
Frequency Distribution ◽  
Cross Section ◽  
Laboratory Tests ◽  
Age Group ◽  
Normal Range ◽  
Cross Sectional ◽  
West Sumatra ◽  
Severity Of The Disease

Malaria is one of the health problems in Indonesia, especially West Sumatra. Determination of the description of Malaria disease in an area is needed to determine the spread and severity of the disease. This study aims to determine the frequency distribution according to age, sex and place of residence, description of the types of Plasmodium causes of Malaria and hematological features in Malaria patients at Siti Rahmah Padang Hospital in 2018. This type of research is a descriptive observational study with an approach or design cross section (cross sectional). The frequency distribution of Malaria sufferers in Siti Rahmah Padang Hospital in 2018 according to the highest age was in the age group 21-30 years as many as 28 cases (36.8%), the highest sex among men was 46 (60.5%) and the highest number of residences was found in Koto Tangah sub-district there were 31 cases (40.8%). The type of Plasmodium found in Malaria cases in Siti Rahmah Padang Hospital in 2018 was P. vivax (73 cases (96.05%)) and P. falciparum (3 cases (3.95%)). The results of laboratory tests on Hb, hematocrit, platelet and leukocyte levels in Malaria positive patients in Siti Rahmah Padang Hospital in 2018 were in the normal range.

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