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

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.

1967 ◽  
Vol 40 (5) ◽  
pp. 1305-1310 ◽  
Author(s):  
G. Kraus ◽  
K. W. Rollmann

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.


1948 ◽  
Vol 26a (2) ◽  
pp. 29-38 ◽  
Author(s):  
J. C. Arnell ◽  
G. O. Henneberry

The modified Kozeny equation has been found to be satisfactory for the measurement of the specific surfaces of carbon blacks having average particle diameters ranging from 0.01 to 0.1 μ to within ±10%. Comparative data were obtained from electron microscope counting and from low temperature nitrogen adsorption isotherms. The three methods examined gave results that were in satisfactory agreement, except when the carbon black was porous, and then the adsorption value was extremely large.


2009 ◽  
Vol 25 (3) ◽  
pp. 165-186
Author(s):  
Abhijit Adhikary ◽  
Pranab Kumar Sengupta ◽  
Rabindra Mukhopadhyay

A simple technique adopted in the laboratory is able to attach flexible, long-chain, aliphatic, fatty acid moiety on the surface of reinforcing carbon black N330. Modified blacks show less bound rubber by comparison with the control, but their better dispersibility effectively outweighs any reduction in polymer–filler interaction resulting from the smaller available surface area. When subjected to strain sweep, compounds containing modified blacks show a slower reagglomeration rate of filler aggregates compared with the control. The lower viscosity of compounds containing modified blacks indicates improved processability.


2007 ◽  
Vol 26-28 ◽  
pp. 301-304
Author(s):  
Shuang Ye Dai ◽  
Ge You Ao ◽  
Myung Soo Kim

Carbon blacks were used as catalysts for hydrogen production through hydrocarbon decomposition. The aim of this work is to find suitable conditions for decomposition reaction to cut down the net cost of hydrogen production. Carbon blacks after hydrocarbon decomposition under different operation conditions were mixed with NBR rubber. The surface area of carbon black increased with low weight gain in methane decomposition caused by carbon deposits on the surface of carbon black aggregates, and the decrease of surface area with further weight gain might be due to the carbon deposits adhering to each other and forming bigger aggregates. The same results were gotten from decomposition of mixture gas of methane and propane. The surface area of carbon black always decreased with the development of propane decomposition reaction. With the same carbon black loading, the composites filled by carbon blacks with low weight gain in methane and methane-propane mixture gas decompositions showed higher tensile strength than those mixed with raw carbon blacks, but there were no significant differences in 300% modulus. With the increase of carbon blacks loading in all composites, 300% modulus and tensile strength always increased. The surface resistivity of composites showed that it was much easier for carbon blacks with low weight gain in methane and methane-propane mixture gas decompositions to dissipate well in the in rubber system.


1979 ◽  
Vol 52 (4) ◽  
pp. 748-763 ◽  
Author(s):  
A. G. Veith ◽  
V. E. Chirico

Abstract This comprehensive program clearly shows the influence of the four defined reinforcement system variables. The tread wear testing conducted over an extremely wide severity range illustrates how the influence of each variable or factor changes as the tire use of test severity is changed. The quantitative influence of the four variables is best illustrated by the index severity gradient, while the index range serves as a quick indicator. The influence of each factor of the reinforcement system increases as general test severity is increased. Carbon blacks with high structure and surface area are substantially superior to blacks with normal structure and surface area at the higher test severities. At the higher general severities, increased oil content produces higher wear rates. At any given severity level, the rate of wear passes through a minimum as carbon black level is increased. The carbon black content at this minimum wear rate shifts to higher values as general severity is raised. Test results at a series of specific cornering force levels (0.10–0.30 g range) indicate that the relative wear of typical tread compounds demonstrates crossovers of index values. Compounds that show superior wear resistance compared to a reference compound at high cornering severities often show inferior wear resistance at low cornering severities. Therefore, for maximum tread life or wear resistance, the reinforcement system with any tread rubber or rubber blend must be carefully adjusted to the anticipated level of tire use severity. The introduction of improved-technology carbon blacks with increased rubber-black interaction that is promoted by high DBP and EMA levels is a substantial advancement in rubber materials science and is most important for the production of high-performance long-treadlife tires.


1981 ◽  
Vol 54 (1) ◽  
pp. 124-133 ◽  
Author(s):  
S. F. Chen

Abstract Soap titration of polymer latex is a widely used method for the determination of the specific surface area and particle size in synthetic latices. The method involves the titration of a latex of known polymer and soap content with a standard soap solution until the critical micelle concentration (CMC) is reached. At this concentration, saturation adsorption of the soap to form a monolayer on the particle surface occurs. From a knowledge of the amount and kind of soap adsorbed and the effective molecular area of the soap on the surface, the specific surface area and average diameter of the particles can be calculated. The effective molecular area of soap at saturation adsorption on polymer particle surface has been determined by comparing adsorption data with particle size data obtained by electron microscopy. Little information is available on the adsorption of sodium dodecyl sulfate (SDS) on NR latex particles. In ammoniated latex, these particles are covered by a complex mixture of proteins, fatty acid soaps, and lipids, the composition and concentration of which are not known accurately. Cockbain modified the soap titration method of determining particle sizes in synthetic latices and claimed that it was applicable to NR latices. In this method SDS was titrated to the latex adjusted to pH 6 ± 0.2. It was assumed that at this pH the interfacial activity of SDS was high while that of the proteins and fatty acid soaps initially present on the latex particles was comparatively low. Under these conditions the SDS would displace almost all the proteins and fatty acid soaps on the particles when sufficient SDS has been added to form micelles in the aqueous phase. The specific surface area was calculated from the SDS adsorption after assuming the molecular adsorption area of SDS to be 60 A˚. No account was taken of the effect of the poly(vinyl alcohol) creaming agent on adsorption. Sekhar found that Cockbain's method of soap titration was temperature dependent. Van den Tempel has shown that electron microscopy cannot yield accurate specific surface area of NR latex particles because of the heterogeneous particle size distribution inherent in unconcentrated latex.


1953 ◽  
Vol 26 (4) ◽  
pp. 862-868
Author(s):  
G. J. van Amerongen

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.


1959 ◽  
Vol 32 (4) ◽  
pp. 1164-1170 ◽  
Author(s):  
W. L. Hawkins ◽  
R. H. Hansen ◽  
W. Matreyek ◽  
F. H. Winslow

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.


1971 ◽  
Vol 44 (5) ◽  
pp. 1287-1296 ◽  
Author(s):  
Jay Janzen ◽  
Gerard Kraus

Abstract Various methods for estimating specific areas of carbon blacks are compared. These include the electron microscope count, methods based on adsorption of nitrogen, iodine and surfactants, and optical reflectance tests.


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