STUDIES OF CARBON BLACK: IV. THE CHANNEL PROCESS—THE EFFECT OF DRAFT CONTROL AND CHANNEL HEIGHT ON RUBBER REINFORCEMENT, SORPTION, AND VOLATILE CONTENT

1937 ◽  
Vol 15b (5) ◽  
pp. 187-207
Author(s):  
L. M. Pidgeon
Keyword(s):  
Methylene Blue ◽  
Carbon Black ◽  
Important Variable ◽  
Channel Height ◽  
Gas Composition ◽  
Direct Relation ◽  
Volatile Content ◽  
High Sorption ◽  
Very High ◽  
Channel Type

In an experimental carbon black plant of the channel type, the effect of channel height, draft control and gas composition on the properties of the carbon has been examined. The channel height was shown to be the most important variable. The rubber reinforcement and the yield of the carbon vary in a similar manner with the channel height at which the carbon was recovered. The sorption of the iodine and methylene blue increased almost logarithmically with the channel height. No direct relation between reinforcement and sorption is possible over the whole range, although the very high sorption obtained at greater channel heights was accompanied by a retarded cure. Sorption was increased by heating the blacks. The volatile content is high at low channel heights, passing through a minimum at the point of optimum yield. This test showed even poorer correlation with rubber reinforcement. Apparent density varied directly with channel height.The effect of draft control upon reinforcement, sorption, and volatile content was indefinite. However, the volatile content seemed to vary directly with the yield. No effects characteristic of the gas composition were found.

STUDIES OF CARBON BLACK: II. THE CHANNEL PROCESS—PRODUCTION FROM THE NATURAL GAS OF TURNER VALLEY, ALBERTA

1936 ◽  
Vol 14b (4) ◽  
pp. 127-137
Author(s):  
L. M. Pidgeon
Keyword(s):  
Methylene Blue ◽  
Natural Gas ◽  
Carbon Black ◽  
Hydrogen Sulphide ◽  
Experimental Plant ◽  
Channel Process ◽  
Carbon Blacks ◽  
Commercial Carbon ◽  
Channel Type

The production of carbon black in an experimental plant of the channel type is described. Carbon black has been produced from Turner Valley dry gas in yields as high as 1.3 lb. per 1000 cu. ft. The rubber reinforcing properties, methylene blue sorption, and per cent extractable are similar to those of the commercial carbon blacks available at present. The presence of hydrogen sulphide in the gas has been examined, but little effect on yields and properties was noticed with concentrations as high as 1% by volume.

Mixing of Carbon Black with Rubber. VI. Analysis of NR/SBR Blends

1988 ◽  
Vol 61 (4) ◽  
pp. 609-618 ◽  
Author(s):  
George R. Cotten ◽  
Lawrence J. Murphy
Keyword(s):  
Molecular Weight ◽  
Carbon Black ◽  
High Molecular Weight ◽  
Surface Area ◽  
Bound Rubber ◽  
Very High

Abstract The distribution of carbon black in NR/SBR blends was determined through the analysis of bound rubber. The NR/SBR blends were found to be very different from the previously studied SBR/BR compounds: these differences were assigned to mutual insolubility of the two polymers and a very high molecular weight of NR. In NR/SBR blends, it was found that changes in molecular weight of the polymer has no effect on the carbon black distribution in the blend. While the “activity” of carbon black did not affect the distribution, the loading of the black in NR decreased linearly with increasing surface area of the black. Approximately 35% of normal tread blacks (surface area 80–100 m2/g) was found in the NR phase. However, the bond between NR and carbon black is quite weak, and black continues to migrate into the SBR phase on prolonged mixing or during blending of NR and SBR masterbatches.

Molecular Weight Effects in Adsorption of Rubbers on Carbon Black

1968 ◽  
Vol 41 (5) ◽  
pp. 1256-1270 ◽  
Author(s):  
Gerard Kraus ◽  
J. T. Gruver
Keyword(s):  
Molecular Weight ◽  
Carbon Black ◽  
Large Particle ◽  
Molecular Weights ◽  
Molecular Weight Dependence ◽  
Bound Rubber ◽  
Sieve Effect ◽  
High Structure ◽  
Very High ◽  
Poor Solvent

Abstract The molecular weight dependence of the adsorption of polybutadiene on carbon black from a poor solvent, n-heptane, and bulk, i.e., the phenomenon of “bound rubber”, was investigated. For narrow distribution polymers the adsorption is proportional to Mn, where n = 0.14 for adsorption from n-heptane solution; n = 0.5 for adsorption from bulk. Anomalously low solution adsorption was observed for polymers of very high molecular weight (> 500,000). This is ascribed to a sieve effect by aggregates of carbon black particles which cannot be penetrated by the large molecular coils. In high structure blacks, which pack more loosely, and in large particle blacks, which form larger interstices between particles, onset of anomalous adsorption is shifted toward higher molecular weights.

Oxidation of Unvulcanized Rubber. Effect of Carbon Black

1954 ◽  
Vol 27 (3) ◽  
pp. 695-704
Author(s):  
F. Lyon ◽  
K. A. Burgess ◽  
C. W. Sweitzer
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Benzoyl Peroxide ◽  
Volatile Content ◽  
Oxidation Reactions ◽  
Reaction Conditions ◽  
Effective Antioxidant ◽  
Opposite Behavior ◽  
Special Case

Abstract The effect of carbon black on the autocatalytic stage of oxidation of unvulcanized rubber is shown to be specific for the type of carbon, the reaction conditions, and the polymer. Carbon black is an effective antioxidant for cold rubber when the rubber is heated in air or oxygen. The effectiveness of carbon in inhibiting oxidation increases as the volatile content of the carbon increases. The special case of low loadings of highly oxidized carbons, which completely repress gelation during Banbury mixing, is of particular interest. The opposite behavior of carbon black during rubber gelation is observed when benzoyl peroxide is used as catalyst. With cold rubber, carbon black promotes gelation, while with natural rubber increased scission results. Alteration of any one of these variables produces profound changes in the course and extent of the oxidation reactions.

New Process for Preparing Tire Tread Compounds Having Low Rolling Resistance

1982 ◽  
Vol 10 (1) ◽  
pp. 16-22 ◽  
Author(s):  
H. Hirakawa ◽  
A. Ahagon
Keyword(s):  
Carbon Black ◽  
Rolling Resistance ◽  
High Carbon ◽  
Two Stage ◽  
Second Stage ◽  
Polybutadiene Rubber ◽  
New Process ◽  
Chlorobutyl Rubber ◽  
Very High ◽  
Wet Skid Resistance

Abstract Two-stage mixing when applied to blends of Chlorobutyl Rubber (C1-IIR), Natural Rubber (NR), and Polybutadiene Rubber (BR), can produce tread compounds exhibiting a combination of very low hysteresis, good wet skid resistance, and good abrasion resistance. In the first stage, about half the raw rubber, including all C1-IIR and BR, is mixed with most of the carbon black to form a very high carbon black stock. In the second stage, the first-stage stock is diluted with the remaining NR. Curatives, etc., are added on the mill. Tests on radial tires for automobiles confirm the advantages of the two-stage mixed tri-rubber blend tread compounds.

scholarly journals The Oxytocin Product Correlates with Total Oxytocin Received during Labor: A Research Methods Study

2017 ◽  
Vol 35 (01) ◽  
pp. 078-083 ◽  
Author(s):  
Lauren Lewis ◽  
Tracy Manuck ◽  
Terrence Allen ◽  
Andra James ◽  
Aurelien Seco ◽  
...  
Keyword(s):  
Total Dose ◽  
Clinical Studies ◽  
Infusion Rate ◽  
Total Duration ◽  
Area Under The Curve ◽  
Important Variable ◽  
Human Labor ◽  
Oxytocin Infusion ◽  
Surrogate Measure ◽  
Very High

Objective Total dose of oxytocin received during labor is an important variable in studies of human labor but is difficult to calculate. We sought to identify a surrogate measure for total dose of oxytocin received. Study Design For each subject receiving oxytocin during labor, the oxytocin total dose received in labor was calculated as the area under the curve. Maximal oxytocin infusion rate, total duration of oxytocin infusion, and the product of both, defined as the oxytocin product, were then each correlated with the total dose of oxytocin received using the Pearson's correlation coefficient. Results Oxytocin dosing data were available from 402 women at Duke and 6,907 women from Pithagore6. The two variables alone, or combined as the oxytocin product, demonstrated a high correlation with the oxytocin total dose (r > 0.7), with the oxytocin product demonstrating the highest (r > 0.9). This was true whether labor was induced or augmented and whether delivery was vaginal or cesarean. Conclusion The oxytocin product, composed of two easily obtained variables, demonstrated a very high correlation with total oxytocin dose received in labor and represents a simple and accurate surrogate for total dose of oxytocin received during labor. The oxytocin product can be used in clinical studies in which oxytocin dose is an important variable.

scholarly journals Evaluation of Fillers Dispersion Degree in Elastomeric Magnetic Composites

2012 ◽  
Vol 2012 ◽  
pp. 1-8
Author(s):  
Ján Kruželák ◽  
Sybill Ilisch ◽  
Ivan Hudec ◽  
Rastislav Dosoudil
Keyword(s):  
Carbon Black ◽  
Butadiene Rubber ◽  
Curing Process ◽  
Magnetic Composites ◽  
Reinforcing Effect ◽  
Rubber Compounds ◽  
Dispersion Degree ◽  
Elastomeric Materials ◽  
Mutual Change ◽  
Very High

Elastomeric magnetic composites were prepared by incorporation of strontium ferrite into polymer matrices based on natural as well as butadiene rubber. Besides the rubber and ferrite, or the combinations of ferrite and carbon black (in case of natural rubber), the model rubber compounds contained only ingredients which support curing process. The study was dedicated to the observation of fillers dispersion degree in the rubber matrices and investigation of physical-mechanical and magnetic properties of prepared composites. The results indicate that the dispersion degree of ferrite in the rubber matrices is not very high, but it can be positively influenced by the addition of carbon black. Despite of the fact that ferrite exhibits only low reinforcing effect on cross-linked elastomeric materials, physical-mechanical properties can be also positively influenced by the mutual change in combinations of both fillers (ferrite and carbon black). The prepared materials seem to have suitable magnetic and elastic properties.

scholarly journals Removal of Methylene Blue from Aqueous Effluent Using Fixed Bed of Groundnut Shell Powder

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Sunil Kumar ◽  
V. Gunasekar ◽  
V. Ponnusami
Keyword(s):  
Methylene Blue ◽  
Low Cost ◽  
Fixed Bed ◽  
Thomas Model ◽  
Bed Height ◽  
Aqueous Streams ◽  
Aqueous Effluent ◽  
Groundnut Shell ◽  
Shell Powder ◽  
Very High

Removal of methylene blue from aqueous solution using a low-cost adsorbent groundnut shell powder (GNSP) was studied using fixed bed. Bed service depth model and Thomas model were employed to study the adsorption kinetics and to predict break-through curves for the system. Both models fit the experimental data very well with very highR2values. Percentage color removal increased with increase in bed height. It was found that adsorption potential of GNSP was in the range of 0.238 to 0.272 kg/kg of adsorbent. These results show that the GNSP can be effectively used as low-cost alternate adsorbent for the removal of pollutants from aqueous streams.

Experiments on the Determination of the Activity of Carbon Black by Its Power of Adsorbing Carbon Tetrachloride Vapor

1940 ◽  
Vol 13 (2) ◽  
pp. 437-440
Author(s):  
T. Patryn
Keyword(s):  
Aqueous Solution ◽  
Carbon Tetrachloride ◽  
Carbon Black ◽  
Reliable Method ◽  
High Ratio ◽  
Point Of View ◽  
Adsorptive Capacity ◽  
The Relationship ◽  
Very High

Abstract On the basis that a material like carbon black must, because of its very high ratio of surface area to volume, possess very high adsorptive capacity, several investigators have attempted to establish the relationship between the adsorptive capacity of carbon black and its activity in rubber. Spear and Moore used aqueous solutions of malachite green, Victoria blue and hexamethylenetetramine; Beaver and Keller used iodine in aqueous potassium iodide; Goodwin and Park used iodine in carbon tetrachloride and also an aqueous solution of methylene blue; Carson and Sebrell used iodine, benzoic acid, mercaptobenzothiazole and diphenylguanidine. All these workers tested various types of carbon black. If one examines critically the data of these several investigators from the point of view of the relation between the adsorptive capacity of a carbon black and its activity in rubber, it will be evident that the investigations do not lead to any reliable method whereby the behavior of carbon black in rubber can be judged by its adsorptive capacity.

Thermal Conductivity of Elastomer Vulcanizates by Differential Scanning Calorimetry

1982 ◽  
Vol 55 (1) ◽  
pp. 191-207 ◽  
Author(s):  
Anil K. Sircar ◽  
John L. Wells
Keyword(s):  
Thermal Conductivity ◽  
Particle Size ◽  
Carbon Black ◽  
Polymeric Materials ◽  
High Concentration ◽  
Scanning Calorimetry ◽  
Relationship Of ◽  
Particle Size And Structure ◽  
Thermal Conductivity Λ ◽  
Very High

Abstract A du Pont 990 differential scanning calorimeter was modified to measure thermal conductivity of elastomer vulcanizates. The method is quick and reproducible and is recommended for scouting research of polymeric materials. The thermal conductivity λ values obtained by this method of some known materials compare favorably with those in the literature. Carbon black increases λ values in all elastomers. Particle size and structure of carbon black seem to affect λ values erratically, although the trend is towards higher λ values with larger particle size and higher structure. A linear relationship of λ vs. volume concentration of carbon blacks and other fillers is observed, except at a very high concentration. The extrapolated values of λ for a filler differ in different elastomeric media. Noncompatible elastomer blends increase or decrease λ values according to the nature and proportion of elastomers. The effect of the manner of addition of carbon black does not seem to affect the λ value of compatible blends. Higher temperatures decrease λ values for all the vulcanizates studied.

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