Influence of carbon black with different polar groups on the solvent N‐methylmorpholine N‐oxide

Regeneration of Carbon Black from Waste Automobile Tyres and its Use in Carcass Compound

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/147776060502100104 ◽

2005 ◽

Vol 21 (1) ◽

pp. 55-72 ◽

Cited By ~ 4

Author(s):

Nilkanta Mandal ◽

Saikat Das Gupta ◽

R. Mukhopadhyaya

Keyword(s):

Carbon Black ◽

Cure Rate ◽

Elongation At Break ◽

Polar Groups ◽

High Adhesion ◽

Heat Treated ◽

Waste Tyres ◽

Environmentally Sound ◽

Real Challenge ◽

Lower Cure Rate

Post-consumer tyre provide a real challenge for recovery and re-use, since they must be disposed of in an environmentally sound and sustainable manner. Pyrolysis has proved an attractive method. The authors have already established a process of pyrolysis to regenerate the carbon black from waste tyres; it was elaborated in an earlier paper. The regenerated blacks(RB) have now been characterized by various methods. They were mixed in a typical virgin carcass compound, the required properties of the mixed compounds were measured, and then the compounds were cured under standard conditions of time and temperature. The physico-mechanical properties of the cured specimens were measured and compared to those of samples made using virgin (VB) and heat-treated blacks (HTB). It was concluded that the regenerated black has a higher surface area, and gives a higher elongation at break, with a higher heat build up, lower cure rate and lower modulus than virgin blacks, but a comparable state of cure, dispersion, hardness, tensile strength, tear strength and high adhesion strength. It was also found that regenerated black had a slightly different structure and agglomerate size. Some polar groups were incorporated into the carbon black, either during pyrolysis or during heat treatment. The regenerated black gave better ageing properties than the virgin or heat-treated blacks.

Download Full-text

Electrical Conductivity of Thermo-Oxidatively-Degraded EPDM Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3538614 ◽

1992 ◽

Vol 65 (2) ◽

pp. 315-328 ◽

Cited By ~ 21

Author(s):

Bengt Mattson ◽

Bengt Stenberg

Keyword(s):

Electrical Conductivity ◽

Electrical Properties ◽

Carbon Black ◽

Percolation Threshold ◽

Oxidative Degradation ◽

Dc Conductivity ◽

Carbonyl Groups ◽

Epdm Rubber ◽

Polar Groups

Abstract Oxidative degradation of rubbers, and the development of oxidized layers at the surfaces, results in increased electrical conductivity. This paper shows that for EPDM rubbers heavily oxidized at 200° C, the DC-conductivity increases more than two orders of magnitude, and the percolation threshold for DC conductivity is decreased below 5 phr carbon black. The effect of oxidation upon the electrical properties is explained as being due to the presence of polar groups, e.g., carbonyl groups, in between the carbon-black agglomerates which provide shorter distances for the electrons to tunnel through.

Download Full-text

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064852 ◽

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.

Download Full-text

Microscopic versus process parameters in heavy-oil upgrading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012223x ◽

1992 ◽

Vol 50 (1) ◽

pp. 366-367

Author(s):

V.A. Munoz ◽

R.J. Mikula ◽

C. Payette ◽

W.W. Lam

Keyword(s):

Molecular Weight ◽

Liquid Fuels ◽

Chemical Components ◽

Heavy Oils ◽

Synthetic Fuels ◽

High Hydrogen ◽

Optical Texture ◽

Polar Groups ◽

Anisotropic Character ◽

Planar Molecules

The transformation of high molecular weight components present in heavy oils into useable liquid fuels requires their decomposition by means of a variety of processes. The low molecular weight species produced recombine under controlled conditions to generate synthetic fuels. However, an important fraction undergo further recombination into higher molecular weight components, leading to the formation of coke. The optical texture of the coke can be related to its originating components. Those with high sulfur and oxygen content tend to produce cokes with small optical texture or fine mosaic, whereas compounds with relatively high hydrogen content are likely to produce large optical texture or domains. In addition, the structure of the parent chemical components, planar or nonplanar, determines the isotropic or anisotropic character of the coke. Planar molecules have a tendency to align in an approximately parallel arrangement to initiate the formation of the nematic mesophase leading to the formation of anisotropic coke. Nonplanar highly alkylated compounds and/or those rich in polar groups form isotropic coke. The aliphatic branches produce steric hindrance to alignment, whereas the polar groups participate in cross-linking reactions.

Download Full-text

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163332 ◽

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.

Download Full-text