ISSN:
0032-3888
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Changes in volume resistivity with temperature of carbon-black-filled polymers and a random copolymer of styrene and butyl methacrylate were measured. For polystyrene containing 20 wt % carbon black, of surface area 24 m2/g, the resistivity changes abruptly from 1013 to 106 ohm-cm above 150°C. Poly(butyl methacrylate) did not show well-defined changes in resistivity on heating. The random copolymer containing 16.7 or 28.6 wt % carbon black, of surface area 24 m2/g, showed a resistivity exceeding 1013 ohm-cm, that decreased to about 107 ohm-cm on heating above 120°C. This Copolymer containing 16.7 wt % carbon black, of surface area 625 m2/g, shows a resistivity of about 108 ohm-cm that decreases sharply to 103 ohm-cm by 150°C. Decreases in resistivity on increasing the temperature in the quiescent state are correlated with the observation of a yield stress at low shear rates in rheological studies. It is suggested that carbon black agglomerates at elevated temperature and forms an independent conductive network that prevents flow.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pen.760280110
