Influence of Carbon Black on the Oxidation of Natural Rubber

1953 ◽  
Vol 26 (4) ◽  
pp. 862-868
Author(s):  
G. J. van Amerongen
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Natural Rubber ◽  
Oxidation Reaction ◽  
Catalytic Action ◽  
Particle Sizes ◽  
Carbon Blacks ◽  
Aging Resistance ◽  
Solubility Of Oxygen

Abstract In this investigation an attempt was made to determine to what extent the solubility of oxygen in natural rubber and the aging resistance are influenced by the incorporation of carbon blacks of various particle sizes in the rubber. The influence of the particle size of carbon black on the oxidizability of GR-S loaded with carbon black had already been proved by Winn, Shelton, and Turnbull. In their explanation of this effect, carbon black was considered to be a catalyst for the oxidation reaction of rubber, although nothing was known about the nature of this catalytic action. Moreover, measurements with natural rubber were lacking.

Measurement of Average Particle Size of Fine Pigments

1932 ◽  
Vol 5 (2) ◽  
pp. 202-215 ◽  
Author(s):  
S. D. Gehman ◽  
T. C. Morris
Keyword(s):  
Particle Size ◽  
Zinc Oxide ◽  
Carbon Black ◽  
Wave Length ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Carbon Blacks ◽  
Count Method

Abstract A method of obtaining excellently dispersed suspensions of rubber pigments of accurate concentration is described in which the pigment is milled into rubber and the stock then dissolved in a solvent. The average particle sizes of carbon blacks measured by the Zsigmondy count method were found to range from 0.061μ for rubber gas black to 2.22μ for the coarsest one measured. The zinc oxide pigments had average particle sizes from 0.076μ to 0.57μ.. Measurements on several other pigments of interest are included. Because of the high visibility in the ultra-microscope, this method gives smaller values for average particle size than the photomicrographic methods. The results have been used to calibrate a microturbidimeter of the extinction type for use in measuring average particle size. Curves are included showing how the turbidities of suspensions of zinc oxide and carbon black vary with the average particle size, concentration, and wave length of light used.

THE ADSORPTION OF SODIUM MYRISTATE BY CARBON BLACK

1949 ◽  
Vol 27f (11) ◽  
pp. 426-428 ◽  
Author(s):  
Marguerite A. Reade ◽  
A. S. Weatherburn ◽  
C. H. Bayley
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Fatty Acid ◽  
Carbon Black ◽  
Surface Area ◽  
Activated Charcoal ◽  
Carbon Blacks ◽  
Preferential Adsorption

The adsorption of sodium myristate from 0.1% aqueous solution by a series of carbon blacks and an activated charcoal has been measured at 70 °C. In every case a preferential adsorption of fatty acid was observed. The extent of adsorption of both the fatty acid and alkali components of the soap increased with decreasing particle size, i.e., with increasing surface area, of the carbons. The adsorption by activated charcoal was considerably higher than that obtained with even the finest of the carbon blacks.

Reactions of Polymers in Bulk. I. Influence of Fillers on the Degree of Crosslinking of Natural Rubber

1962 ◽  
Vol 35 (3) ◽  
pp. 563-571 ◽  
Author(s):  
J. Janacek
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Specific Surface ◽  
Contact Surface ◽  
Chemical Nature ◽  
Chain Structure ◽  
Filler Concentration ◽  
Carbon Blacks

Abstract The relation between the degree of crosslinking determined by means of swelling and the theoretical total contact surface of rubber to carbon black was investigated with vulcanizates of two elastomers which were cured by various vulcanization methods and using various concentrations—even extremely high ones—of carbon blacks with different specific surface, degrees of chain structure and chemical activities. A constant, α, the magnitude of which generally depends upon the degree of agglomeration of the carbon blacks and on the chemical nature of their surface as well as on the polymers used and the vulcanization method, but which is practically unrelated to the filler concentration, has been proposed to express the relative crosslinking activity of carbon blacks.

Ozone and Sunlight Effect on Aging of Carbon Black Vulcanizates

1953 ◽  
Vol 26 (1) ◽  
pp. 127-135
Author(s):  
George E. Popp ◽  
Lynn Harbison
Keyword(s):  
Particle Size ◽  
Low Temperature ◽  
Carbon Black ◽  
Natural Rubber ◽  
Size Structure ◽  
Synthetic Polymer ◽  
Ozone Exposure ◽  
Polymer Compound ◽  
Type Particle ◽  
Weather Resistance

Abstract Carbon black, regardless of type, particle size, structure, and physical properties imparted, does not affect the rate or degree of checking or cracking in natural-rubber or low-temperature polymer compounds when subjected to weather or ozone exposure. Natural rubber will withstand much longer periods of exposure than the synthetic polymer studied. A pronounced degree of ozone and weather cracking and checking will result if no antioxidant is compounded into the synthetic polymer. An MAF black-synthetic polymer compound may be substantially improved in its resistance to ozone and weather resistance by selection and application of the proper antichecking ingredients.

Carbon Black Surface Areas by the Harkins and Jura Absolute Method

1967 ◽  
Vol 40 (5) ◽  
pp. 1305-1310 ◽  
Author(s):  
G. Kraus ◽  
K. W. Rollmann
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Surface Area ◽  
Nitrogen Adsorption ◽  
Absolute Method ◽  
Carbon Blacks ◽  
Surface Areas ◽  
Particle Size Determination ◽  
Light Reflectance ◽  
Adsorption Surface

Abstract The Harkins and Jura (HJ) absolute method of surface area determination (Harkins and Jura, J. Am. Chem. Soc. 66, 919, 1944) has been applied to a large number of carbon blacks. Surface area is calculated from the heat of immersion of the solid powder covered by a preadsorbed multilayer of the immersion liquid. For non-porous carbon blacks good agreement with nitrogen adsorption surface areas is obtained, but with porous blacks the HJ method gives smaller values since micropores are filled and bridged over by the pre-adsorbed film. Thus the HJ areas are more nearly representative of particle size and may be used to calibrate indirect methods of particle size determination. An example of this is shown using light reflectance values on dry carbon black and possible complications due to particle size distribution in the use of the reflectance test are discussed.

Determination of Particle Size in Latex

1953 ◽  
Vol 26 (2) ◽  
pp. 481-486 ◽  
Author(s):  
E. G. Cockbain
Keyword(s):  
Particle Size ◽  
Sodium Dodecyl Sulfate ◽  
Natural Rubber ◽  
Sodium Dodecyl ◽  
Average Particle ◽  
Particle Sizes ◽  
Sulfate Concentration ◽  
Titration Method ◽  
Dodecyl Sulfate

Abstract The soap titration method of determining average particle sizes in synthetic latexes has been modified so as to make it applicable to natural rubber latexes. The method consists essentially in determining the distribution of an added detergent (sodium dodecyl sulfate) between the rubber and aqueous phases at a pH of approximately 6.0, the total dodecyl sulfate concentration being just sufficient for the formation of micelles in the aqueous phase. The average particle sizes of nine ammoniated latexes have been measured, including centrifuged and electrodecanted concentrates, two clonal field latexes and a sample of latex skim.

Investigations of Rubber Fillers. I. Particle Size and Characteristic form of Carbon Blacks and Their Influence on the Properties of Rubber Mixtures, as Judged by Ultra-Microscopic Photographs

1941 ◽  
Vol 14 (4) ◽  
pp. 920-928
Author(s):  
Th. Schoon ◽  
H. W. Koch
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
The Other ◽  
Particle Sizes ◽  
Characteristic Form ◽  
Electron Microscopic ◽  
Rubber Industry ◽  
Characteristic Shape ◽  
Carbon Blacks ◽  
The Past

Abstract The particle sizes and characteristic shapes of the particles of eighteen blacks used in the rubber industry were determined. The values which were obtained are compared with the physical properties of rubber mixtures prepared from these blacks. The characteristic shape of the particles has the greatest effect on the extensibility and the rigidity at 200 per cent elongation, i.e., on the modulus. When the particle size of a black is over 100 mµ, relatively poor resistance to tearing of vulcanizates containing the black is obtained. In general, the particle size of a black has far less influence on the other physical properties than has been believed in the past. With the aid of electron microscopic photographs, it is possible to estimate the value of a black as a filler in rubber.

Effect of Carbon Black Substitution with Raw and Modified Bentonite on the Thermal Aging Resistance of Natural Rubber Composites

2016 ◽  
Vol 705 ◽  
pp. 8-13 ◽  
Author(s):  
Clare L. Garing ◽  
Bryan B. Pajarito
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Tensile Properties ◽  
Thermal Aging ◽  
Clay Platelet ◽  
Aging Resistance ◽  
Contour Plots ◽  
Activated Bentonite ◽  
Simplex Lattice ◽  
Simplex Lattice Mixture Design

The effect of carbon black (CB) substitution with raw (BNT) and modified (M-BNT) bentonite on the thermal aging resistance of natural rubber (NR) composites was investigated in this study. NR composites were prepared at varied proportions of CB, M-BNT, and BNT using a three-component, third degree simplex lattice mixture design of experiment (DOE). M-BNT was produced by modifying sodium-activated bentonite with tetradecyldimethylamine (TDA) salt and cocamide diethanolamine (CDEA). Thermal aging was performed at 70 and 100°C for 168 and 336 h. Substitution of CB with 5 phr M-BNT gave the highest values of tensile properties (modulus and strength) for both unaged and aged samples. This is attributed to the synergistic effect of CB and M-BNT fillers on the tensile properties of NR composites. In terms of property retention (%), composites filled with M-BNT and BNT clay fillers attained the highest values which signified their excellent thermal aging resistance. This observation proves the barrier effect of clay platelet structure which hinders oxygen diffusion in the rubber. Reduced hierarchical models as function of CB, M-BNT, and BNT proportions were used to generate contour plots for tensile properties of NR composites after 168 h of aging at 70 and 100°C.

The Influence of Carbon Black on the Reversion Process in Sulfur-Accelerated Vulcanization of Natural Rubber

1982 ◽  
Vol 55 (1) ◽  
pp. 103-115 ◽  
Author(s):  
C. H. Chen ◽  
J. L. Koenig ◽  
J. R. Shelton ◽  
E. A. Collins
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Carbon Black ◽  
Natural Rubber ◽  
Linear Function ◽  
Operating Conditions ◽  
Universal Curve ◽  
Black Particle ◽  
System Operating

Abstract The effect of carbon black upon the reversion process in the sulfur-accelerated vulcanization of natural rubber has been studied. It is found that black-filled cure systems have a faster rate of vulcanization and better reversion resistance. The net decrease of trans-methine content, which is equivalent to the improvement of reversion resistance, is found to be at most 15%, with the initial 10 pphr loading yielding the greatest effect. However, those decreases of trans-methine content are small when compared with the substantial effects of these fillers on the physical-mechanical properties of the vulcanizate, which is a linear function of black loading. In general, the smaller the black particle size, the greater the improvement of the reversion resistance, but particle size alone is not the only factor affecting reversion. A universal curve is obtained for correlating the amount of reversion and trans-methine content, which is independent of any natural rubber-based curing system, operating conditions and type of fillers.

The Effect of Carbon Black on Thermal Antioxidants for Polyethylene

1959 ◽  
Vol 32 (4) ◽  
pp. 1164-1170 ◽  
Author(s):  
W. L. Hawkins ◽  
R. H. Hansen ◽  
W. Matreyek ◽  
F. H. Winslow
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Chemical Nature ◽  
Antioxidant Effect ◽  
Carbon Surface ◽  
Carbon Blacks ◽  
Wide Ph Range ◽  
Black Surface ◽  
Phenol Antioxidants ◽  
Ph Range

Abstract Carbon black has been shown to function as a mild thermal antioxidant for polyethylene at 140° C. The amount of protection increases with concentration and is dependent on the chemical nature of the carbon surface. This antioxidant effect is shown by a variety of carbon blacks with a considerable range of particle size, but very coarse carbons in comparable weight concentration exhibit no antioxidant effect. Recent studies concerned with the chemical nature of the carbon black surface indicate the presence of various oxygenated groupings which may account for the weak antioxidant activity of some carbon blacks. In all cases examined, conventional amine and phenol antioxidants in polyethylene are adversely affected by carbon black. This effect can be attributed to adsorption followed by chemical decomposition of the antioxidant on the carbon black. The chemical nature of the carbon black apparently influences the adsorption since the loss in activity of amine antioxidants is much more pronounced with acidic than basic carbon blacks. Whereas the effect of carbon black on antioxidant behavior is observed over a wide pH range, the effect decreases and finally disappears as the particle size of the carbon black is increased.

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