The Effect of Fillers on the Permeability of Rubber to Gases

1955 ◽  
Vol 28 (3) ◽  
pp. 821-832 ◽  
Author(s):  
G. J. Van Amerongen
Keyword(s):  
Carbon Black ◽  
Oxygen Adsorption ◽  
High Rate ◽  
Considerable Decrease ◽  
Rubber Mixture ◽  
Carbon Blacks ◽  
Energy Factors ◽  
Reinforcing Fillers ◽  
Inorganic Fillers ◽  
Mechanical Nature

Abstract The purpose of the investigation was to study the effects of fillers, especially various types of carbon black and new light-colored reinforcing fillers. In the discussion of the problem, it is shown that permeability to gases is related to the rate of diffusion, and to the solubility of the gas in rubber, and it is also shown how these properties were measured. The effect of carbon black on the permeability of rubber to gases is relatively small. Independent of the type of carbon black, the permeability is reduced only about 30 per cent by the addition of 50 parts by weight of carbon black per 100 parts of rubber. The permeability of a rubber mixture to a gas is increased considerably, however, by the presence of fine types of carbon blacks, while the rate of diffusion of the gas is decreased. This fact can be explained by assuming that gas is adsorbed by carbon black in rubber and thereby rendered inactive. The high oxygen adsorption of the finer types of carbon blacks in rubber mixtures explains the high rate of oxidation of such mixtures. A whole series of inorganic fillers, among them some light-colored reinforc- ing agents, have no noteworthy effect on permeability. With 20 parts by volume of such fillers per 100 parts of rubber, the permeability is decreased only about 25 per cent, irrespective of the particular filler. A considerable decrease of permeability, i.e., about 75 per cent, is observed, however, with lamellar fillers, such as powdered aluminum and powdered mica. A rubber mixture containing powdered mica shows, at 100° C, the same permeability to hydrogen and nitrogen that Butyl rubber does. The relation of permeability to the temperature of rubber containing fillers is practically the same as that for an unloaded rubber mixture. The decreases of permeability to gases which are observed, are, therefore, not related to energy factors, but are of a purely mechanical nature.

Structure and Properties of Loaded Rubber Mixtures. IX. Modification of Carbon Structures by Repeated Deformations

1953 ◽  
Vol 26 (4) ◽  
pp. 810-820 ◽  
Author(s):  
K. Pechkovskaya ◽  
Ts Mil'man ◽  
B. Dogadkin
Keyword(s):  
Carbon Black ◽  
Small Proportion ◽  
Electric Resistivity ◽  
Structural Development ◽  
Carbon Structure ◽  
Rubber Mixture ◽  
Carbon Blacks ◽  
Opposite Case ◽  
Carbon Carbon Bonds ◽  
Carbon Bonds

Abstract 1. The structure of the carbon black phase of a rubber-carbon black vulcanizate is characterized first of all by a specific number of rubber-carbon black and carbon black-carbon black bonds (or contacts) and, in turn, by a specific proportion of these two types of bond. 2. The total number of bonds in the carbon structure, or the degree of their development, is indicated by the specific electric resistivity ρ of the vulcanizate, which decreases with the development of this structure. 3. Measurement of the proportion of carbon-carbon bonds in the structure establishes the factor n of the equation I=CVn, relating the energy of the current which flows through the test-specimen to the constant by the difference of the potentials. If n=1, all the bonds in the carbon structure which take part in the transmission of the current are of the carbon-carbon type, and the rubber mixture possesses a purely ohmic conductivity; in all other cases n>1. 4. During the deformation of loaded vulcanizates, changes of the specific resistivity ρ, and also of the factor n, take place. In the first cycle of stretching, ρ at first increases and then decreases slightly. During recovery after stressing, the electric resistivity sharply increases, reaching after the stress is removed a value several times greater than the maximum on the p curve of the first cycle of deformation. In succeeding deformation cycles, the change of resistivity proceeds with relatively slight hysteresis effects. 5. In the deformation of loaded rubbers, the weaker bonds are largely destroyed, and consequently the proportion of bonds of the stronger type increases. In cases where the carbon-carbon bonds are stronger than the rubber-carbon bonds, the value of n after deformation is smaller than that of n0 before deformation, or n0/n>1; in the opposite case, n0/n<1. 6. Both parameters (n and ρ) depend on the type of rubber; their greatest values, corresponding to a less developed structure with a small proportion of carbon-carbon bonds, are observed in the case of butadiene-styrene rubber; in sodium-butadiene rubbers, the degree of structural development and proportion of carbon-carbon bonds are much higher; the most highly developed carbon structure and the greatest proportion of carbon-carbon bonds are found in Butyl and natural rubbers. Hence, the value of n0/n is hardly related to the type of rubber. 7. Both parameters also depend on the type of carbon black. The most highly developed structures, with a large proportion of carbon-carbon bonds, are observed with channel carbon black, where these bonds are stronger than the rubber-carbon bonds, i.e., n0/n>1. The least developed structure, with a small proportion of carbon-carbon bonds, is observed with nozzle black and lampblack, in which cases these bonds are weaker than the rubber-carbon bonds, i.e., n0/n<1. Furnace blacks occupy an intermediate position. Thus, the carbon blacks studied are classified according to the value of n and the relation n0/n in the same sequence as when classified according to their reinforcing effects. The possible causes of this distribution are discussed. 8. The great strength of the bond between the particles of more active (channel) carbon blacks is one of the reasons for the greater heat formation in rubbers containing these carbons. Heat formation in rubbers containing less active carbon blacks (nozzle black, lamp black) which possess a weaker bond between their particles when all other conditions are equal, is much less.

Filler Aggregates and Their Effect on Reinforcement

1974 ◽  
Vol 47 (2) ◽  
pp. 411-433 ◽  
Author(s):  
A. I. Medalia
Keyword(s):  
Carbon Black ◽  
Fine Particles ◽  
High Surface ◽  
High Surface Area ◽  
Experimental Studies ◽  
Spherical Particles ◽  
Rubber Compound ◽  
Carbon Blacks ◽  
Reinforcing Fillers ◽  
Aggregate Nature

Abstract The most highly reinforcing fillers, namely carbon blacks and silicas, consist of aggregates of quasi-spherical particles fused together. In the absence of direct experimental studies with single-particle carbon blacks or silicas of high surface area, we cannot be sure if aggregated structure is essential for good reinforcement, or whether aggregation and fusion just happen to accompany the formation of fine particles at practical concentrations. In any case, there is no doubt that the aggregate nature of the filler plays a major role in determining the properties of the rubber compound. Here I would like to review what we know about filler aggregates, especially of carbon black, and suggest some mechanisms for their effects on rubber; and also indicate where our knowledge seems inadequate at the present time.

Filler Choices in the Rubber Industry

1982 ◽  
Vol 55 (3) ◽  
pp. 860-880 ◽  
Author(s):  
E. M. Dannenberg
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Size Range ◽  
Carbon Black Particle ◽  
Silane Coupling Agents ◽  
Particle Size Range ◽  
Calcium Carbonates ◽  
Rubber Industry ◽  
Carbon Blacks ◽  
Inorganic Fillers

Abstract A wide variety of inorganic fillers are produced for the rubber industry. The most important are the clays, precipitated silicas and silicates, and the ground and precipitated calcium carbonates. The silicas and silicates provide the broadest particle size range falling into the carbon black range from FEF (N550) to finer than SAF (N110). The clays and calcium carbonates are in the larger carbon black particle size range from coarser than thermal black (N990) to FEF (N550). if particle size were the only important parameter determining the usefulness of rubber fillers, these products would meet the requirements presently served by carbon black. Their failure to be interchangeable with the carbon blacks is due to their lower modulus and reinforcement performance. These deficiencies are caused by the nature of their surfaces, which are generally more polar and hydrated than carbon black. This makes them more difficult to adhere to and interact with the rubber phase. In order to improve the surface interaction of inorganic fillers with hydrocarbon rubbers, a number of new polymer-reactive, surface-treated products have been introduced. The addition of silane coupling agents during mixing has also been recommended. Silane treated clays and talc, and polymer-grafted clay and calcium carbonate are commercially available. These products are better than their base materials. For some applications, they have been suggested as alternatives to the lower reinforcing grades of carbon black. For the higher reinforcing carbon blacks, only the precipitated silicas with silane additives can be considered as alternatives. However, in tire tread applications, the performance of these combinations has not been clearly defined, and the high cost of the silanes makes their use with silica prohibitive. A more economic method for coupling may result from recent research on functionalized polymers capable of reacting with the surface silanol groups of silica. This survey also includes two finely divided carbonaceous fillers made from coal and petroleum coke. Blends of these materials with more reinforcing carbon blacks and other fillers have been recommended as alternatives to the carbon blacks in the thermal to SRF range. A number of commercial fillers have been suggested as alternatives to the lower reinforcing grades of carbon black for some applications. There are no satisfactory substitute products for the medium to high reinforcing grades of carbon black.

Effect of Carbon Blacks on Swelling of Neoprene GRM-10 Vulcanizates

1949 ◽  
Vol 22 (3) ◽  
pp. 812-819 ◽  
Author(s):  
N. L. Catton ◽  
D. C. Thompson
Keyword(s):  
Carbon Black ◽  
Natural Rubber ◽  
Physical Properties ◽  
Compression Modulus ◽  
Tension Stress ◽  
Limited Extent ◽  
Carbon Blacks ◽  
Reinforcing Fillers ◽  
Swelling Characteristics ◽  
Natural Rubber Vulcanizates

Abstract Reinforcement of elastomers with fillers has generally been measured by physical properties, such as tension stress-strain, tear resistance, hardness, and compression modulus. To a more limited extent, swelling in solvents has been recognized as associated with reinforcement. In natural-rubber vulcanizates it has been demonstrated that reinforcing fillers impart greater resistance to solvents and oils than do nonreinforcing types. Addition of the latter gives only the reduction in swelling attributable to elastomer dilution. In the case of Neoprene vulcanizates, Catton and Fraser reported that fillers function only as elastomer diluents and that those fillers commonly considered as of the reinforcing type impart no greater resistance to solvents than the nonreinforcing type. More recently, however, Buist and Mottram, in describing the effects of carbon blacks on the physical properties of natural rubber and Neoprene, reported that with both of these elastomers compounds containing thermal type carbon black gave slightly greater swelling in benzene than compounds containing equal loadings of other types of carbon black. With Neoprene, they reported good correlation between moduli and swelling characteristics.

The influence of oxidized technical carbon N121 on the properties of butyl-based rubbers

2019 ◽  
pp. 123-128
Author(s):  
M. N. Nagornaya ◽  
A. V. Myshliavtsev ◽  
S. Ya. Khodakova
Keyword(s):  
Hydrogen Peroxide ◽  
Carbon Black ◽  
Gas Permeability ◽  
Mechanical Tests ◽  
Butyl Rubber ◽  
Rubber Mixture ◽  
Active Forms Of Oxygen ◽  
Technical Carbon ◽  
Furnace Black ◽  
The Subject

The subject of the study were samples of channel technical carbon K354, furnace technical carbon N121 and experimental – based on TUN121, oxidized with active forms of oxygen. Samples of carbon black were studied in the composition of a rubber mixture based on BK 1675N butyl rubber. The purpose of this study was to determine the possibility of using oxidized technical carbon N121 in fillers of rubber based on butyl rubber, instead of carbon black K354. The physicochemical properties of the samples of technical carbon under study, the results of physical and mechanical tests, and the gas permeability tests of rubber mixtures filled with the samples under study are presented. A conclusion is made about the possibility of replacing channel technical carbon K354 with furnace black carbon N121 oxidized with 30% hydrogen peroxide.

Ionic Crosslinking of Carboxylated SBR

1983 ◽  
Vol 56 (5) ◽  
pp. 942-958 ◽  
Author(s):  
Kyosaku Sato
Keyword(s):  
Zinc Oxide ◽  
Carbon Black ◽  
Elevated Temperatures ◽  
Ion Clusters ◽  
Ionic Crosslinking ◽  
Reinforcing Fillers ◽  
Ionic Bonds ◽  
Tan Δ ◽  
And Shifts ◽  
Ionic Crosslinks

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.

Interfacial Interactions in Silica Reinforced Silicones

1989 ◽  
Vol 170 ◽  
Author(s):  
Mirta I. Aranguren ◽  
Christopher W. Macosko ◽  
Bima Thakkar ◽  
Matthew Tirrell
Keyword(s):  
Low Molecular Weight ◽  
Complex Structures ◽  
Small Particles ◽  
Carbon Blacks ◽  
Silica Surfaces ◽  
Reinforcing Fillers ◽  
Fractal Characteristics ◽  
Physical Forces ◽  
A New Technique ◽  
Silicone Rubbers

AbstractThe study of the type and strength of the filler-polymer linkages is of great importance in understanding the reinforcement of elastomers. Silicone rubbers are weak elastomers and the addition of reinforcing fillers is essential in order to obtain useful, strong materials. The best reinforcing filler for these elastomers are fumed silicas. These fillers, like reinforcing carbon blacks, have very complex structures. Both have fractal characteristics, small particles fused together forming open aggregates that can cluster by physical forces. Silicas have sometimes more complex structures than carbon blacks, but have a better understood surface chemistry. Interactions between polydimethylsiloxanes and silica surfaces have been studied using heat of adsorption measurements of mostly low molecular weight analogs or inferring the strength of the adsorption by the shift of particular peaks in the infrared spectrum [1]. Here we will present a new technique that measures directly the strength of the adsorption of the polymer segments onto glass and between themselves. It also allows for comparison of the strength of such bonds with the strength of a polymer entanglement “link”.

Mixing and Comparative Properties of NR Compounds Filled with Different Types of Reinforcing Fillers

2017 ◽  
Vol 266 ◽  
pp. 172-176
Author(s):  
Pattarawadee Maijan ◽  
Nitinart Saetung ◽  
Wisut Kaewsakul
Keyword(s):  
Carbon Black ◽  
Silica Surface ◽  
High Viscosity ◽  
Cure Rate ◽  
Modified Silica ◽  
Reinforcing Fillers ◽  
Silane Coupling ◽  
Different Types ◽  
Cure Time

Mixing behaviors of the compounds filled with different reinforcing fillers were studied in correlation with compound and vulcanizate properties. Four filler systems were used including: 1) silica plus small amount of silane coupling agent; 2) carbon black; 3) pre-modified silica; and 4) silica+silane-carbon black mixed one. The results have shown that silica provides longer optimum cure time and shorter cure rate than carbon black due to accelerator adsorption on silica surface. In addition, owing to highly polar nature on silica surface the silica-based compounds show rather high viscosity, attributed to stronger filler-filler interaction as can be confirmed by Payne effect and reinforcement index. However, the commercial surface treatment or pre-modified form of silica shows superior properties than in-situ modification of silica by silane during mixing, while it gives comparable properties to carbon black-based compound. Tensile properties of vulcanizates show a good correlation with the basic properties of their compounds.

A Carbon Black Structure-Concentration Equivalence Principle. Application to Stress-Strain Relationships of Filled Rubbers

1971 ◽  
Vol 44 (1) ◽  
pp. 199-213 ◽  
Author(s):  
Gerard Kraus
Keyword(s):  
Carbon Black ◽  
Primary Structure ◽  
Equivalence Principle ◽  
Chemical Activity ◽  
Cross Linking ◽  
Surface Chemical ◽  
Deformation Structure ◽  
Carbon Blacks ◽  
Filled Rubbers ◽  
Dependent Factor

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.

Enhancing oxygen adsorption capabilities in Li–O2battery cathodes through solid perfluorocarbons

2017 ◽  
Vol 5 (27) ◽  
pp. 14152-14164 ◽  
Author(s):  
Moran Balaish ◽  
Yair Ein-Eli
Keyword(s):  
Carbon Black ◽  
Room Temperature ◽  
Nitrogen Adsorption ◽  
Oxygen Adsorption ◽  
Electrochemical Investigation ◽  
Liquid Adsorption

Perfluorocarbons, solid at room temperature, were added at different weight ratios to carbon black-based air electrodes for Li–O2battery. PFCs-modified air-electrodes showed improved battery performance and were characterized by HRSEM images, nitrogen adsorption (BET), liquid adsorption, a comprehensive wettability study and electrochemical investigation.

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