ENSACO® Conductive Carbon Black for polymer ... - Timcal Graphite

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10 The selection of a conductive carbon black NENSACO ® Conductive Carbon Blacks find their applications in an unlimited number of plastics. The combination of the polymer type and grade and the carbon black grade are determining the overall electrical and mechanical performance. NThe main parameter influencing the final conductivity of a finished part in a given polymer is the type and level of carbon black used. NThe higher the structure of the carbon black, the lower the level of carbon black needed to achieve the required conductivity. Nevertheless, in a minor way, other parameters like the additives in presence, the compounding or processing conditions may also influence the final conductivity of parts. NLow surface area conductive carbon blacks show a particular advantage on dispersion and processing. NPercolation curves – correlating the volume resistivity and the carbon black percentage – are a useful comparative tool to predict the conductivity in place and to select the more appropriate system. These curves are valid for a given formulation and sample preparation technique. NThe selection of the conductive carbon black will also influence: the compounding behaviour (dispersibility, resistance to shear, mixing cycle, melt flow index, extrusion throughput); the surface appearance of the finished material (number of surface defects); the mechanical properties (polymer property retention, reinforcement); the overall price – performance ratio. www.timcal.com Typical applications for ENSACO ® Conductive Carbon Black Electrically conductive plastics The preparation of a conductive compound NSuitable mixing equipments for the preparation of black conductive compounds include internal mixers, twin screw extruders, single screw kneader machines and LCM. The feeding of low bulk density, soft flake-type carbon blacks into extruders requires the use of twin screw feeders and separate introduction on an already molten polymer (split feeding technology). Some typical final plastics applications: handling of electronic components: carrier boxes, carrier trays, carrier tapes, etc.; films: antistatic and conductive films, packaging films, garbage bags, etc.; automotive industry: fuel injection systems, anticorrosion systems, fuel tank inlet, electrostatically paintable parts, etc.; transport: mobile phone parts, wheels, containers, bins, pallets, etc.; computer: antistatic articles for computer & accessories, CD player, etc.; health: medical applications, cleanroom equipments, articles for antistatic workplaces, etc.; antistatic flooring; heating element; sensors; PTC switches; UV protection and pigmentation. In the following pages there are some of the results of experimental work carried out on ENSACO ® Conductive Carbon Blacks in different polymer compounds. The data shown here are given as orientation and are valid for the particular formulations and sample preparation technique mentioned. Results in other polymers, full studies and publications are available upon request.
ENSACO ® Conductive Carbon Blacks in HDPE Volume Resistivity (Ohm.cm) Volume Resistivity (Ohm.cm) Volume Resistivity (Ohm.cm) 10 9 10 7 10 5 10 3 10 0.1 0 800 700 600 500 400 300 200 100 0 4 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 4 Various carbon blacks in HDPE E 250 E 260 E 350 10 20 30 40 50 % Carbon Black Concentration (%) Resistivity vs mixing time - 18% carbon black E 250 E 260 5 6 7 8 9 10 Brabender Mixing Time (min) Resistivity vs mixing time - 25% carbon black E 250 E 260 5 6 7 8 9 10 Brabender Mixing Time (min) Influence of the carbon black type on the resistivity: Compounding: laboratory Brabender internal mixer. Processing: compression moulding. The higher the structure of the carbon black, the lower the percolation threshold. At a concentration very near to the percolation level, when overmixed, ENSACO ® 260 G offers a higher consistency in resistivity resulting from its higher shear stability in extreme working conditions. At a concentration far above the percolation level, both blacks are very stable in resistivity when overmixed. ENSACO ® 260 G shows a consistent lower resistivity. 11
Page 1 and 2: Graphite Carbon Black Carbon additi
Page 3 and 4: TIMREX ® Graphite and ENSACO ® Ca
Page 5 and 6: Introduction to TIMREX ® Graphite
Page 7 and 8: Typical effects on polymer compound
Page 9: Typical effects on polymer compound
Page 13 and 14: ENSACO ® Conductive Carbon Blacks
Page 15 and 16: NBR conductive hose compound NBR NT
Page 17 and 18: Typical applications for ENSACO® C
Page 19 and 20: Incorporation of graphite powder in
Page 21 and 22: Influence of TIMREX ® Graphite and
Page 23 and 24: Typical applications for TIMREX® G

ENSACO® Conductive Carbon Black for polymer ... - Timcal Graphite

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