Carbon Black Structure and the Tear Resistance of Vulcanizates

1959 ◽  
Vol 32 (4) ◽  
pp. 1180-1184
Author(s):  
V. G. Epshtein

Abstract 1. The increase in tear resistance of vulcanizates, where carbon blacks are added in considerable amounts, is related to the formation of secondary black structures and is manifested especially when certain blacks are used (channel, anthracene and acetylene). 2. The presence of secondary black structures brings about an increase in the tear resistance at elevated temperatures.

1983 ◽  
Vol 56 (5) ◽  
pp. 942-958 ◽  
Author(s):  
Kyosaku Sato

Abstract 1. Ionic bonding of carboxylated SBR with zinc oxide is detectable by means of measurements of the temperature dependence of tan δ. There is an α peak in the region of 60°C at 3.5 Hz. The position and shape of the α peak are strongly dependent on the state of cure of the vulcanizates. Without permanent crosslinking, the α peak is a plateau; as the crosslink density increases, the α peak becomes sharper and shifts to lower temperatures. The presence of carbon black causes the α peak to shift to higher temperatures, regardless of the presence of permanent crosslinks. 2. Ionic bonds in carboxylated SBR reacted with zinc oxide are in the form of ion clusters which function as crosslinks at room temperature. The ionic crosslinks provide carboxylated SBR with high tensile strength in the absence of reinforcing fillers. The presence of carbon black causes the 300% modulus to increase. The ionic crosslinks are labile, and the strength is lost at moderately elevated temperatures. A mixed cure system consisting of both sulfur and zinc oxide provides higher heat resistance than either of the single cure systems.


1971 ◽  
Vol 44 (1) ◽  
pp. 199-213 ◽  
Author(s):  
Gerard Kraus

Abstract It is shown that various modulus values of carbon black reinforced rubber are functions of the product of the actual black loading and a structure dependent factor. The structure factor appears to be a linear function of the so-called 24M4 value of the dibutylphthalate absorption and is independent of elongation, temperature, and degree of cross-linking over the ranges covered by the data reported. An interpretation of the results is offered based on the idea of polymer occluded in the interstices of primary structure aggregates and thereby shielded from deformation. Structure-concentration equivalence can only be demonstrated with carbon blacks differing in (primary) structure alone. Deviations are observed whenever the carbon blacks compared vary significantly in specific surface area and surface chemical activity.


1944 ◽  
Vol 17 (2) ◽  
pp. 451-474
Author(s):  
D. Parkinson

Abstract Carbon blacks can be grouped into different classes according to the way in which their fineness of division relates to different properties in rubber. Within any one class the principal properties vary in a regular manner with particle size. The normal class consists of the furnace carbons, Kosmos (Dixie)-40, Statex, the rubber-grade impingement carbons, and possibly, the color-grade impingement carbons. The subnormal classes consist of thermal carbons and acetylene and lamp blacks. Irrespective of the above classification, the properties which depend more on fineness of division than on other factors are rebound resilience, abrasion resistance, tensile strength and tear resistance. The lower limit of particle diameter for best tensile strength and tear resistance appears to be higher than that for abrasion resistance. B.S.I, hardness and electrical conductivity are properties which depend at least as much on other factors as on particle size. Stiffness (modulus) depends more on other factors than on particle size. Factors modifying the effects of particle size (or specific surface) include the presence of carbon-carbon structures and a reduction in strength of bond in rubber-carbon structures. Carbon black is thought to exist in rubber in four states: agglomerated, flocculated, dispersed, and bonded to the rubber molecules (the reënforcing fraction). Abrasion resistance is regarded as providing the only reliable measure of reënforcement.


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.


2011 ◽  
Vol 84 (4) ◽  
pp. 493-506
Author(s):  
Irene S. Yurovska ◽  
Michael D. Morris ◽  
Theo Al

Abstract Racing tires and motorcycle tires present individual segments of the tire market. For instance, while the average life of car and truck tires is 50 000 miles, the average life of race tires is 100 miles. Because tires play a critical role in a race, technical demands to assure safety and performance are growing. Similarly, tires have a large influence on safety, handling/grip, and performance of the rapidly growing world fleet of motorcycles, due to the fact of only two wheels being in contact with the ground. Thus, the common feature of both market segments is that the typical tire compromise of wear, rolling resistance, and traction is strongly weighted toward traction. Most of the recent efforts of rubber scientists have been directed toward lowering rolling resistance of the tread compounds, which left a certain void in the science of compounding for racing and motorcycle treads. Particularly, the industrial assortment of polymers and fillers used for motorcycle treads is commonly different from that used for car or truck treads, but it is not known how the filler properties affect the hysteresis–stiffness compromise. The objective of this study is to evaluate the effects of the carbon black characteristics on the important properties of a typical racing and motorcycle tire tread compound. More than 50 individual carbon blacks were mixed in a SBR formulation. The acquired data were statistically analyzed, and a linear multiple regression model was developed to relate rubber properties (responses), such as static modulus, complex dynamic modulus, hysteresis, and viscosity to the key carbon black characteristics (variables) of surface area, structure, aggregate size distribution, and surface activity. Prediction profiles created from the model demonstrate rubber performance limits for the range of carbon blacks tested, and indicate the niches to provide required combinations of the rubber properties.


1936 ◽  
Vol 14b (4) ◽  
pp. 127-137
Author(s):  
L. M. Pidgeon

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.


RSC Advances ◽  
2020 ◽  
Vol 10 (68) ◽  
pp. 41837-41845
Author(s):  
Sunil Kumar ◽  
Dongwoon Kang ◽  
Hyeryeon Hong ◽  
Malik Abdul Rehman ◽  
Yeon-jae Lee ◽  
...  

The effect of Ti3C2Tx MXene etched at different temperatures (25 °C, 50 °C, and 80 °C) on the capacitance of supercapacitors without the use of conducting carbon-black or a binder was studied.


1953 ◽  
Vol 26 (4) ◽  
pp. 821-831 ◽  
Author(s):  
B. A. Dogadkin ◽  
K. Pechkovskaya ◽  
Ts Mil'man

Abstract 1. Raising the temperature of vulcanizates containing carbon black causes changes in the carbon structures, which can be estimated by the value of specific electric resistivity ρ and the index n in the equation: I=cVn, relating the strength of the current I with the voltage V. 2. These changes are nearly independent of the type of rubber and are governed chiefly by the type of carbon black. 3. The change of electric resistivity of vulcanizates with temperature follows an exponential law, and can be expressed by the equation : ρt=ρ0 eαt. 4. The sign of the coefficient α is negative for vulcanizates containing channel carbon black, and positive for those containing nozzle black or lamp black. 5. Heating of vulcanizates (up to 100°) for 30 minutes causes destruction of the nozzle black and lamp black particles, but causes little apparent destruction of channel black structures. 6. Prolonged heating (10 hours or more) at temperatures above 60° C causes destruction of the particles of all the carbon blacks studied. This detruction is more extensive in the case of nozzle and lamp blacks than in the case of channel black. 7. During heat treatment of mixtures containing channel black, it is chiefly the carbon-rubber bonds that are destroyed (the index n decreases); whereas in mixtures containing nozzle, furnace and lamp blacks, it is chiefly the carbon-carbon bonds that are destroyed (the index n increases). 8. The higher the temperature during deformation and relaxation, the greater is the degree of restoration of the carbon structures which are destroyed during deformation. 9. The degree of restoration of the carbon structures under identical conditions of deformation and relaxation of vulcanizates containing nozzle black is greater than that of corresponding vulcanizates containing channel black.


2002 ◽  
Vol 09 (03n04) ◽  
pp. 1443-1452 ◽  
Author(s):  
C. D. HUANG ◽  
Z. T. XIONG ◽  
J. Y. LIN ◽  
K. L. TAN

In this paper we report the electrochemical behavior of heat-treated carbon blacks and Pt/C catalysts. Cyclic voltammetry indicates that the heat-treated carbon black as catalyst support does not improve the Pt/C catalyst's activity for methanol oxidation. An XPS study of a Pt-loaded carbon black indicates that the amounts of oxidized platinum and oxygen-functional groups on catalysts are decreased when the platinum particles are deposited on the heat-treated carbon surface. These changes in the surface and crystalline structural properties of carbon materials lead to the catalytic activity change in methanol electro-oxidation.


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