The effect of pressure on carbon black/elastomer powders

1975 ◽  
Vol 253 (3) ◽  
pp. 206-219 ◽  
Author(s):  
G. Angerer ◽  
H. Schilling
Keyword(s):  
Carbon Black ◽  
Effect Of Pressure

Effect of Pressure and Shear on Compaction of Powdered Rubber with Carbon Black

1985 ◽  
Vol 58 (2) ◽  
pp. 392-406
Author(s):  
N. Nakajima ◽  
P. R. Kumler ◽  
E. R. Harrell
Keyword(s):  
Carbon Black ◽  
Pressure Range ◽  
Static Pressure ◽  
Lower Pressure ◽  
Bridge Structure ◽  
Capillary Rheometer ◽  
Solid Mass ◽  
Effect Of Pressure ◽  
Rotor Surface ◽  
Powdered Rubber

Abstract During the incorporation stage of mixing carbon black with elastomer, the mixture becomes one solid mass, i.e., compacted. In this process, the elastomer must be deformed to conform with the topology of carbon black. This work attempts to elucidate the mechanism of compaction. In particular, the effects of static pressure and shear on compaction have been examined. A Sieglaff-McKelvey capillary rheometer was used for the higher pressure range and a Rheometrics mechanical spectrometer for the lower pressure range. A mixture of powdered rubber and carbon black was used. With static pressure alone, the compaction was slow and ineffective because the mixture forms a bridge structure. The compacted material was friable. With the application of shear, the bridge structure was easily broken, the compaction was attained immediately, and the compacted material was “fused” together. However, the application of shear was effective only when there was no slip between the rotor surface and the elastomer compound.

Resistivity of Rubber as a function of Mold Pressure

1988 ◽  
Vol 61 (5) ◽  
pp. 828-841 ◽  
Author(s):  
Corley M. Thompson ◽  
T. W. Besuden ◽  
L. L. Beumel
Keyword(s):  
High Pressure ◽  
Electrical Resistivity ◽  
Carbon Black ◽  
Kinetic Data ◽  
Careful Consideration ◽  
Molding Pressure ◽  
Covalent Bonds ◽  
Cure Cycle ◽  
Effect Of Pressure ◽  
Rubber Compounds

Abstract For this N550 carbon black, loaded over a narrow but typically used range, high molding pressure caused a decrease in electrical resistivity of several orders of magnitude. The earlier in the cure cycle the high pressure was applied, the greater was the decrease in resistivity. A suggested mechanism for the effect is the formation of covalent bonds between carbon-black particles that are pushed into closer proximity by the high mold pressure. This postulate is supported by the limited kinetic data available. Clearly, pressure applied to a rubber sample during molding must be given as careful consideration as the loading of carbon black when materials requiring high resistivities are prepared. Although it has not been pursued in this work, the effect of pressure on the electrical resistivity of conductive rubber formulations may be significant. Further work underway is addressing the effect of mold pressure on the electrical resistivity of other rubber compounds as well as loadings of some other types of carbon black.

A Preparation of High Resolution Standards for Electron Microscopy. Part II

1971 ◽  
Vol 29 ◽  
pp. 160-161
Author(s):  
Akira Tanaka ◽  
David F. Harling
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Carbon Black ◽  
Single Crystal ◽  
Dark Field ◽  
Graphitized Carbon Black ◽  
Graphitized Carbon ◽  
Dark Field Imaging ◽  
Crystal Films ◽  
Micro Holes

In the previous paper, the author reported on a technique for preparing vapor-deposited single crystal films as high resolution standards for electron microscopy. The present paper is intended to describe the preparation of several high resolution standards for dark field microscopy and also to mention some results obtained from these studies. Three preparations were used initially: 1.) Graphitized carbon black, 2.) Epitaxially grown particles of different metals prepared by vapor deposition, and 3.) Particles grown epitaxially on the edge of micro-holes formed in a gold single crystal film.The authors successfully obtained dark field micrographs demonstrating the 3.4Å lattice spacing of graphitized carbon black and the Au single crystal (111) lattice of 2.35Å. The latter spacing is especially suitable for dark field imaging because of its preparation, as in 3.), above. After the deposited film of Au (001) orientation is prepared at 400°C the substrate temperature is raised, resulting in the formation of many square micro-holes caused by partial evaporation of the Au film.

Extraction and identification of fillers and pigments from pyrolyzed rubber and tire samples

1996 ◽  
Vol 54 ◽  
pp. 174-175
Author(s):  
P. Sadhukhan ◽  
J. B. Zimmerman
Keyword(s):  
Zinc Oxide ◽  
Electron Microscope ◽  
Carbon Black ◽  
Natural Rubber ◽  
Transmission Electron Microscope ◽  
Rolling Resistance ◽  
Synthetic Polymers ◽  
Nitrogen Atmosphere ◽  
Transmission Electron ◽  
Curing Agents

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.

Effect of pressure on structure and fluorescence of SrFCL: Sm2

1990 ◽  
Vol 3 (1) ◽  
pp. 144-146
Author(s):  
Y. R. Shen ◽  
T. Gregorian ◽  
Th. Tröster ◽  
O. Schulte ◽  
W. B. Holzapfel
Keyword(s):  
Effect Of Pressure
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