Study on Thermal Conductivity of Composites of Rubber/CB with Good Electrical Properties

2011 ◽  
Vol 221 ◽  
pp. 466-471 ◽  
Author(s):  
Jun Ping Song ◽  
Yan He ◽  
Lian Xiang Ma
Keyword(s):  
Thermal Conductivity ◽  
Carbon Black ◽  
Filler Loading ◽  
Graphitized Carbon Black ◽  
Acetylene Black ◽  
Rubber Matrix ◽  
Rubber Composites ◽  
Graphitized Carbon ◽  
The Difference ◽  
Better Than

Graphitized carbon black 40b2 and acetylene black were filled separately in natural rubber matrix for preparing vulcanized rubber. The thermal conductivity of both kinds of composites was studied considering filler loading and temperature. SEM and TEM were applied to observe morphology of the filler and composites. The experimental results show that thermal conductivity of acetylene black/rubber composites is much better than that of graphitized carbon black 40b2/rubber composites, which is opposite to the electric conduction properties. As filler loading increased, the difference increased, and when the filler loading is up to 40phr, the thermal conductivity value of acetylene black/rubber composite is 53% larger than the other one. TEM shows that acetylene black has more botryoidal structure, larger carbon black aggregates in size, and much looser surface than 40b2.Moreover, for acetylene black, particles contact by surface mainly, and for 40b2, particles contact by point mainly. SEM shows that the distribution of carbon black 40b2 in rubber matrix is much better than acetylene black. The better thermal conductivity for acetylene black is attributed to the higher structure, nonuniform distribution in rubber matrix and surface contact between particles.

Percolation Phenomenon in Thermal Conductivity of Carbon Black Filled Rubber and Morphology

2010 ◽  
Vol 146-147 ◽  
pp. 575-580
Author(s):  
Jun Ping Song
Keyword(s):  
Thermal Conductivity ◽  
Carbon Black ◽  
Natural Rubber ◽  
Percolation Threshold ◽  
Volume Fraction ◽  
Graphitized Carbon Black ◽  
Rubber Matrix ◽  
Rubber Composites ◽  
Percolation Behavior ◽  
Percolation Phenomenon

A kind of graphitized carbon black 40B2 was incorporated in natural rubber matrix and vulcanizates were prepared. The content of carbon black varied from 4 to 100phr for 100phr of natural rubber. Thermal conductivity of the CB/rubber composites was studied as a function of CB loadings and temperature. TEM and SEM were employed to explore the morphology of the carbon black and the composites. It was found that percolation phenomenon existed in thermal conductivity of CB/rubber composites at different filler loadings, which was much similar with percolation behavior in electrical conductivity properties of many composites, and the percolation threshold was about 13.63%. The influence of temperature on thermal conductivity was more obviously within the region from the percolation threshold to the volume fraction of 26.2%.However, no great effect could be found on the percolation behavior of the composites in thermal conductivity. The result of TEM indicated that the mean size of CB particles was about 25nm, the maximum size of CB aggregates was about 125nm, and the CB aggregates were multichain in shape. The results of SEM showed that the distribution of CB differed at different filler loadings. Before the percolation threshold, the CB aggregates existed isolatedly, nevertheless at the percolation threshold, some long chains made up of CB aggregates ran through the rubber matrix, which resulted in the rapid increase in thermal conductivity value, and then with the addition of CB loadings, the number of chains increased. When the volume fraction was up to 26.2%, some three dimensional networks formed.

Contribution of Carbon Black to Thermal Conductivity of Natural Rubber

2013 ◽  
Vol 561 ◽  
pp. 158-163 ◽  
Author(s):  
Jun Ping Song ◽  
Lian Xiang Ma
Keyword(s):  
Thermal Conductivity ◽  
Carbon Black ◽  
Natural Rubber ◽  
Filler Loading ◽  
Considerable Improvement ◽  
Middle Level ◽  
Rubber Composites ◽  
Filled Rubber ◽  
The Poor ◽  
Natural Rubber Composites

Eight kinds of carbon black filled natural rubber composites were prepared, and thermal conductivity was studied. Acetylene black contributes much to the thermal conductivity of rubber, and tiny loading results in considerable improvement. The conductive carbon black 40B2 is advantageous for the improvement in thermal conductivity of rubber when its loading reaches middle level, and at its middle level, also tiny loading results in much improvement. Most kinds of carbon black for rubber application filled rubber composites have good properties except for N134 and N660, especially the poor contribution of N660. Additionally, in the case of carbon black filled rubber composites, addition of filler may not necessarily benefit the thermal conductivity when filler loading is not much.

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.

Orthogonal Experiment Analysis of Mechanical Thermal Conductivity on Multi-Component Fillers

2013 ◽  
Vol 753-755 ◽  
pp. 2379-2382
Author(s):  
Shi Meng Xu ◽  
Run Bo Ma ◽  
Jian Hua Du ◽  
Jun Hong Liu ◽  
Qi Jin
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Carbon Black ◽  
Orthogonal Experiment ◽  
Experiment Design ◽  
Rubber Composites ◽  
Orthogonal Experiment Design ◽  
Rubber Composite ◽  
Al Powder ◽  
Experiment Analysis

Filled the N330 carbon black, silica T80 carbon black and Al powder and Fe2O3 magnetic nanoparticles, the rubber composites on multi-component electromagnetic fillers were prepared according to orthogonal experiment analysis, and the preliminary experiment conclusions of the filler prescription designs were given; Based on the experiment design, the mechanical properties and thermal conductivity of the rubber composite were tested, and the testing results were analyzed by using variance analysis. Thus, the paper shows that the effects of N330 on rubber mechanical properties are significant, and the effects of Al powder on the rubber thermal conductivity are significant. Moreover, it is highly emphasized in this paper that the orthogonal experiment design must be carefully explored before the tests are executed.

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