A Kinetics Study on Electrical Resistivity Transition of In Situ Polymer Aging Sensors Based on Carbon-Black-Filled Epoxy Conductive Polymeric Composites (CPCs)

A side-entry type, helium-temperature specimen stage that has the capability of in-situ electrical-resistivity measurements has been designed and developed for use in the AEI-EM7 1200-kV electron microscope at Argonne National Laboratory. The electrical-resistivity measurements complement the high-voltage electron microscope (HVEM) to yield a unique opportunity to investigate defect production in metals by electron irradiation over a wide range of defect concentrations.A flow cryostat that uses helium gas as a coolant is employed to attain and maintain any specified temperature between 10 and 300 K. The helium gas coolant eliminates the vibrations that arise from boiling liquid helium and the temperature instabilities due to alternating heat-transfer mechanisms in the two-phase temperature regime (4.215 K). Figure 1 shows a schematic view of the liquid/gaseous helium transfer system. A liquid-gas mixture can be used for fast cooldown. The cold tip of the transfer tube is inserted coincident with the tilt axis of the specimen stage, and the end of the coolant flow tube is positioned without contact within the heat exchanger of the copper specimen block (Fig. 2).

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Dynamics of Nanoparticle Chain Aggregates of Carbon Under Tension

MRS Proceedings ◽

10.1557/proc-778-u4.4 ◽

2003 ◽

Vol 778 ◽

Author(s):

Rajdip Bandyopadhyaya ◽

Weizhi Rong ◽

Yong J. Suh ◽

Sheldon K. Friedlander

Keyword(s):

Mechanical Properties ◽

Carbon Black ◽

Polymer Film ◽

Elastic Behavior ◽

Small Strains ◽

Transmission Electron ◽

Chain Aggregates ◽

Nanoparticle Chains ◽

Reinforcing Filler

AbstractCarbon black in the form of nanoparticle chains is used as a reinforcing filler in elastomers. However, the dynamics of the filler particles under tension and their role in the improvement of the mechanical properties of rubber are not well understood. We have studied experimentally the dynamics of isolated nanoparticle chain aggregates (NCAs) of carbon made by laser ablation, and also that of carbon black embedded in a polymer film. In situ studies of stretching and contraction of such chains in the transmission electron microscope (TEM) were conducted under different maximum values of strain. Stretching causes initially folded NCA to reorganize into a straight, taut configuration. Further stretching leads to either plastic deformation and breakage (at 37.4% strain) or to a partial elastic behavior of the chain at small strains (e.g. 2.3% strain). For all cases the chains were very flexible under tension. Similar reorientation and stretching was observed for carbon black chains embedded in a polymer film. Such flexible and elastic nature of NCAs point towards a possible mechanism of reinforcement of rubber by carbon black fillers.

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In~situ Kinetics Study in Chemical Vapor Deposition of Pyrocarbon from Propylene

Journal of Inorganic Materials ◽

10.3724/sp.j.1077.2008.01265 ◽

2008 ◽

Vol 23 (6) ◽

pp. 1165-1170

Author(s):

Chun-Nian ZHAO

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Kinetics Study

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Polymer composites as sensing materials for liquid organic solvents – preliminary results

e-Polymers ◽

10.1515/epoly.2011.11.1.362 ◽

2011 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Stanislaw Frackowiak ◽

Monika Maciejewska ◽

Andrzej Szczurek ◽

Marek Kozlowski

Keyword(s):

Electrical Resistivity ◽

Carbon Black ◽

Polymer Composites ◽

Percolation Theory ◽

Liquid Mixtures ◽

Organic Liquids ◽

Volumetric Fraction ◽

Factors Influencing ◽

Benzene Toluene ◽

Main Factors

AbstractCarbon black-filled polymer composites were investigated as sensing materials for organic liquids. Polypropylene and polystyrene which were selected as matrices and various amounts of carbon black were considered as the main factors influencing sensitivity of the composites in view of the percolation theory. Disposable filaments were produced of these materials. Change in their electrical resistivity was measured upon immersion in benzene, toluene, xylene, ethylbenzene and their mixtures. It has been found that studied materials were sensitive to the composition of liquid mixtures of organic solvent. Relationships between the filament response and volumetric fraction of the components were presented. The studied materials have shown promising sensing properties, which suggest their applicability for identification and quantification of multicomponent organic liquids.

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A new development of four-point method to measure the electrical resistivity in situ during plastic deformation

Measurement ◽

10.1016/j.measurement.2021.109547 ◽

2021 ◽

pp. 109547

Author(s):

Saeid Saberi ◽

Martin Stockinger ◽

Christian Stoeckl ◽

Bruno Buchmayr ◽

Helmut Weiss ◽

...

Keyword(s):

Plastic Deformation ◽

Electrical Resistivity ◽

Point Method ◽

New Development

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

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.266.172 ◽

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.

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