scholarly journals Studies of Texaco Carbon Black Particle Surface by Polarography

1963 ◽  
Vol 84 (3) ◽  
pp. 212-214,A16 ◽  
Author(s):  
Shiro TAKASHIMA ◽  
Genzo HASHIZUME ◽  
Itaru MOTOOKA
1970 ◽  
Vol 43 (5) ◽  
pp. 973-980 ◽  
Author(s):  
A. K. Sircar ◽  
A. Voet

Abstract Determinations have been made of the amount of elastomer unextractable from unvulcanized masticated mixes with carbon black by a given solvent at boil, expressed as immobilized elastomer. Saturated and unsaturated elastomers varying in molecular weights from 2000 to 325,000, were used, while solvents of greatly differing boiling points and solvent power were employed. It could be shown that the bonding between elastomers and carbon black is not a simple adsorption, but involves a higher energy interaction, defined as chemisorption. At successively higher temperatures elastomer is increasingly removed from the carbon black surface. The temperature Tm, obtained by extrapolation of the linear relationship between amounts immobilized and temperature of extraction, represents the temperature theoretically required to eliminate all bonds between carbon black and elastomer and is therefore indicative of the bond strength. Data suggest the existence of a bonding energy spectrum. Upon graphitization, blacks show a considerable decline in high energy bonding ability for elastomers. Saturated elastomers show less bonding than unsaturated elastomers with the same furnace black. “Bound rubber” represents the sum total of physically adsorbed, mechanically entangled, and chemisorbed elastomer. The actual values are greatly dependent upon the procedure used. “Immobilized rubber”, indicating chemisorbed elastomer, is easily determined, is not influenced by the method, and is more significant as an indicator of reinforcement.


2011 ◽  
Vol 311-313 ◽  
pp. 201-204
Author(s):  
Hong Zhong Ru ◽  
Ran Ran Zhao

Electrical conductive carbon black-filled cement-based composites are significant as multifunctional structural materials. Double percolation in carbon black-filled cement-based composites involves both carbon black particle percolation and cement paste percolation, which has great effect on the resistivity of composites. Based on double percolation theory, the influences of sand-binder ratio and carbon black volume fraction on the resistivity of carbon black-filled cement-based composites are investigated. The results show that besides carbon black volume fraction, sand-binder ratio is a key factor affecting double percolation behavior in carbon black-filled cement-based composites. At a fixed carbon black content in overall mortar, with increasing sand-binder ratio, the cement paste percolation though aggregate phase increases due to high obstruction of aggregate but the carbon black particle percolation in cement paste decreases. This is because that the microstructure of aggregate is impenetrable so that the carbon black particles are limited in cement paste, that is, the carbon black content in paste is compacted and large amount of conductive paths are generated by lapped adjacent carbon black particles in paste. The double percolation in the electrical conduction in carbon black-filled cement-based composites is observed when the carbon black volume fraction is 7.5% and sand-binder ratio is 1.4, and its resistivity is only 3200 Ωcm, so that a sand-binder ratio of 1.4 and 7.5% carbon black volume fraction or more are recommended for attaining high conductivity with a compromise between workability and conductivity.


1970 ◽  
Vol 43 (2) ◽  
pp. 464-469 ◽  
Author(s):  
P. Aboytes ◽  
A. Voet

Abstract Experimental carbon blacks were prepared with the generally encountered slit-shaped pores of discrete dimensions of 9,12.5, and 16 A˚ width in greatly differing size distribution. Equilibrium adsorption in the saturation range was determined in n-hexane for butadiene—styrene elastomers of the SBR type of average molecular weights of 1500; 2000; 15,000; and 300,000. In attempting to correlate the saturation adsorption values with carbon black surface areas, it was found that a simple linear relation in the range investigated could only be obtained by assuming that pores of 9 A˚ width were inaccessible to SBR of 1500 and 2000 MW; that pores of 9 and 12.5 A˚ width were inaccessible to SBR of 15,000 MW; and that all pores smaller than 20 A˚ width were inaccessible to SBR of 300,000 MW. The data indicated that there are no differences between high, regular and low structure blacks in saturation elastomer adsorption under conditions of equivalent dispersion. Equally, upon breaking the persistent carbon chain structure by dry ball milling in an inert atmosphere and equalizing the chemical surface properties by removal of surface oxides, no difference in elastomer adsorption from solution was observed. It must be concluded that commonly used high molecular elastomers do not have any access to smaller carbon black pores. Since access to the surface is a prerequisite for reinforcement, it is obvious that the surface in the pores of carbon black generally does not participate in reinforcing elastomers. The elastomer adsorbed per unit external black surface area appears to be independent of the carbon chain structure, indicating that the so called surface activity of the carbon black is independent of the chain length.


2014 ◽  
Vol 971-973 ◽  
pp. 178-182
Author(s):  
Nai Xiu Ding ◽  
Yi Jia ◽  
Pei Yan Zuo ◽  
Li Li Wang ◽  
Hai Tao Wang

The curing characteristics,crosslinking density,compressive permanent deformation,the conventional mechanical properties and dynamic mechanical properties of SBR2564S filled with different carbon black were studied.The results indicated that with the increase in specific surface area of carbon black particles,Mooney viscosity of the resulting mixture increased while the scorch time decreased.As the carbon black particle size increases, tensile strength and tear strength of SBR2564S were reduced,rebound and compressive set were increased.The kinds of carbon black had little effect on the crosslinking density of vulcanized rubber of SBR2564S.It had poor performance on dynamic mechanical properties of the resulting mixture filled with small carbon black particle size.SBR2564S vulcanizates with good comprehensive properties was obtained when N330 was used.


1974 ◽  
Vol 47 (1) ◽  
pp. 231-249 ◽  
Author(s):  
E. S. Dizon ◽  
A. E. Hicks ◽  
V. E. Chirico

Abstract Fatigue is defined as decay caused by cyclic deformations at an amplitude less than necessary for fracture in one cycle. Such failures are initiated by flaws which act as stress concentrators. These flaws occur in the material either through mechanical or chemical action during service or through agglomeration of certain ingredients during mixing and fabrication. This paper deals with the latter process, where the nature and size of the flaws as well as the properties of the matrix are contingent on carbon black variables. Using the tearing energy concept of fatigue developed by Lake and Lindley, it was shown that the size of the flaw is primarily determined by carbon black particle size. On the other hand, the cut growth constant depends on carbon black structure. When translated to actual fatigue life using the Monsanto Fatigue-to-Failure Tester, these relationships mean that under constant strain conditions, compounds containing coarse carbons will have a significantly higher fatigue life than those with fine carbons. Under conditions of constant strain, higher structure carbons will impart a slight positive effect. However, under conditions of constant stress, the beneficial effects of structure become magnified. Other factors known to affect fatigue life were also considered. These are : set, stress relaxation, hysteretic energy dissipation, and flaw size distribution.


2009 ◽  
Vol 87-88 ◽  
pp. 200-205 ◽  
Author(s):  
Yan He ◽  
Zhong Yin ◽  
Lian Xiang Ma ◽  
Jun Ping Song

Through measuring the thermal conductivities and tensile strength of nature rubbers filled with carbon black and comparing with each other, it is shown that the difference of carbon black particle size and the structure affects on the thermal conductivity and tensile strength of nature rubber. Thermal conductivities of carbon black-filled nature rubber are enhanced with the increase of volume fraction of filler; tensile strength of composite increases first and then decreases with the increase of carbon black volume fraction.


2014 ◽  
Vol 931-932 ◽  
pp. 1083-1088 ◽  
Author(s):  
Theerapab Tantisakon ◽  
Kanyarat Holasut

The effects of carbon black particle dispersed in the electrolyte and used in a modified VRB which was traditionally used of carbon felt as electrode has been removed were studied. The adding of the carbon black particle reduced both activation overpotential and ohmic overpotential especially at low OCV. The functional group on the surface of the carbon black particle helps to increase the rate of reaction which results in the reduction of activation overpotential. When the electrolyte with the carbon black particle dispersed flows into the cell, it is possible that some of carbon particles settle on the surface of current collectors and this effectively increases the surface area of current collectors. Hence, it reduces the ohmic overpotential.


Sign in / Sign up

Export Citation Format

Share Document