The relationship of carbon black dispersion to electrical resistivity and vulcanizate physical properties

1982 ◽  
Vol 22 (10) ◽  
pp. 601-609 ◽  
Author(s):  
R. J. Cembrola
Keyword(s):  
Electrical Resistivity ◽  
Carbon Black ◽  
Physical Properties ◽  
Relationship Of ◽  
The Relationship ◽  
Carbon Black Dispersion

Investigation of Electromagnetic Interference Shielding Effectiveness of Cement-Based Composites Filled with Carbon Materials

2010 ◽  
Vol 168-170 ◽  
pp. 1021-1024
Author(s):  
Guo Xuan Xiong ◽  
Zhi Bin Zhang ◽  
Min Deng ◽  
Yu Fen Zhou
Keyword(s):  
Carbon Fiber ◽  
Carbon Black ◽  
Electromagnetic Interference ◽  
Carbon Materials ◽  
Shielding Effectiveness ◽  
Nano Carbon ◽  
Electromagnetic Interference Shielding Effectiveness ◽  
Carbon Nano Tube ◽  
Relationship Of ◽  
The Relationship

The cement-based composite shielding materials filled with carbon materials such as ordinary carbon materials (graphite, coke and carbon black), carbon fiber and nano-carbon materials (carbon nano-tube and nano-carbon black) were prepared. The relationship of conductivity and shielding effectiveness in a frequency range of 100 KHz~1.5 GHz was studied. The electric properties of cement-based composites filled with carbon fiber is better than other carbon materials. With the contents of carbon fiber of 5.vol%, the average shielding effectiveness is about 37 dB and the maximum shielding effectiveness reaches 40 dB.

The Direct Determination of Oxygen in Rubber. The Adaptation of the Ter Meulen Method to Rubber and Its Application to the Study of Aging

1939 ◽  
Vol 12 (2) ◽  
pp. 269-282 ◽  
Author(s):  
H. I. Cramer ◽  
I. J. Sjothun ◽  
L. E. Oneacre
Keyword(s):  
Tensile Strength ◽  
Physical Properties ◽  
Direct Determination ◽  
Sulfur Poisoning ◽  
Oxidation Products ◽  
Oxygen Bomb ◽  
Vulcanized Rubber ◽  
Relationship Of ◽  
The Relationship

Abstract The ter Meulen method for the direct determination of oxygen has been adapted, with modifications, to the analysis of raw and vulcanized rubbers. Raney nickel has been found to be quite effective as the reducing catalyst and to be satisfactorily resistant to sulfur poisoning. The method has been applied to the study of the aging of vulcanized rubber in the Geer oven and oxygen bomb. From this study the following conclusions may be drawn: (1) The increase in combined oxygen is greater in the oxygen bomb than in the Geer oven. (2) Deterioration of rubber in the oxygen bomb involves oxidation primarily, whereas that occurring in the Geer oven involves not only oxidation but also thermal decomposition followed by volatilization of oxidation products. (3) The effectiveness of an antioxidant in retarding the absorption of oxygen in oxygen-bomb aging agrees well with its ability to maintain the physical properties of the stock in which it is present. (4) The deterioration in physical properties of a rubber stock in the oxygen bomb during the early stages of aging is a linear function of the increase in combined oxygen. For stocks containing antioxidants and diphenylguanidine as the accelerator, an increase in combined oxygen of approximately 1.2% corresponds to a decrease in tensile strength of 50%. (5) The relationship of increase in combined oxygen to decrease in tensile strength seems to be affected not only by antioxidants, but also by accelerators of vulcanization.

scholarly journals On the Relationship of Thermodynamic and Physical Properties of Polymers With Ice Adhesion

1985 ◽  
Vol 6 ◽  
pp. 146-149 ◽  
Author(s):  
H. Murase ◽  
K. Nanishi
Keyword(s):  
Physical Properties ◽  
Adhesive Strength ◽  
Polymer System ◽  
Work Of Adhesion ◽  
Polymer Composition ◽  
Coating Materials ◽  
The Difference ◽  
Relationship Of ◽  
The Relationship ◽  
Ice Adhesion

The purpose of this work is to study the relationship of energetic and physical properties of polymetric materials with ice adhesion, and to develop the material to prevent ice adhesion. From various parameters of water and ice, dispersion and hydrogen bond contribution of surface free energy of ice were calculated. Using these values and that of contact angle formed between Ice and polymer in the air and also in paraffin, work of adhesion W-πe and W were determined respectively. The difference W-(W-πe ) has made it possible to evaluate the effect of surface pressure n on ice adhesion. On the other hand, actual adhesive strength of ice was measured. Some correlations between theoretical and observed values were found. Further, visco-elastic properties of polymers below icing temperature and temperature dependence of strain in the ice/polymer system were investigated. The results showed some characteristics of polymers which are related to molecular mobility at lower temperature, are effective in reducing the adhesive strength to ice. Numerous attempts were made to develop coating materials to prevent ice adhesion. A composite polymer composition, which has peculiar ingredients and structure, was proposed and found to provide the ability for the lowest ice adhesion. Ice preventive mechanism of the film was discussed.

Electrical resistivity of fluorinated carbon black

1988 ◽  
Vol 3 (5) ◽  
pp. 890-897 ◽  
Author(s):  
Matthew H. Luly
Keyword(s):  
High Pressure ◽  
Electrical Resistivity ◽  
Carbon Black ◽  
Physical Properties ◽  
Surface Structure ◽  
Pressure Dependence ◽  
Rapid Change ◽  
Fluorine Content ◽  
Aggregate Structure ◽  
Fluorinated Carbon

The electrical resistivity of fluorinated carbon black particles, CFx, is reported as a function of fluorine content, pressure, and temperature. Fluorination does not destroy the aggregate structure of carbon black, but does change its physical properties. The resistivity changes from 10−2 to 10+12 Ω cm as x increases from 0 to 1.2, with a very rapid change occurring in the range 0.08≤x≤0.27. Samples with x = 0 and x = 0.07 exhibit a pressure dependence described by p∝ P−s with s>0. Fully fluorinated samples (x = 1.2) have s≃0. Intermediate compositions have low-pressure regimes where the resistivity is independent of pressure, and high-pressure regimes with s>0. For all samples exhibiting pressure-dependent resistivity, s increases as x increases. For samples with low-fluorine content, the resisitivity increases with decreasing temperature. These observations are interpreted in terms of structure, especially surface structure.

Chemistry in Carbon Black Dispersion

1955 ◽  
Vol 28 (1) ◽  
pp. 202-212
Author(s):  
Bernard C. Barton ◽  
Hugh M. Smallwood ◽  
George H. Ganzhorn
Keyword(s):  
Carbon Black ◽  
Physical Properties ◽  
Chemical Bonding ◽  
Physical Nature ◽  
Surface Characteristics ◽  
Beneficial Effects ◽  
Strong Adsorption ◽  
Black Surface ◽  
Reticulate Structure ◽  
Carbon Black Dispersion

Abstract The properties of carbon black and their effect on the physical properties of rubber vulcanizates have been extensively reported. The importance of particle size, reticulate structure, and surface characteristics are generally accepted. The beneficial effects of carbon black are believed to be due in large part to strong adsorption of rubber molecules on the carbon black surface. Many investigators have described the physical nature of this adsorption and have related it to the surface properties of the carbon black. Chemical bonding has also been suggested as being an important factor in the surface interaction between carbon black and rubber. The contribution of chemical bonding to the dispersion of carbon black and its effect on the physical properties of vulcanizates is the subject of the present paper. Gerke, Ganzhorn, Howland, and Smallwood and Bradley found almost twenty years ago that, when rubber-carbon black mixtures were heated at temperatures of 275–400° F, vulcanizates prepared from the mixtures had lower electrical conductivity, lower hysteresis, lower durometer hardness, higher modulus at large deformations, and greater resistance to abrasion than did vulcanizates of the corresponding unheated mixtures. These changes were ascribed to changes in the dispersion of the carbon black. Experimental data will be presented in this paper which suggest that these changes in carbon black dispersion are the result of chemical reactions between carbon black and rubber.

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