A FINE DISTINCTION: CARBON BLACK

Currently, the American Society for Testing and Materials (ASTM) D 5596 Standard Test Method for Microscopic Evaluation of the Dispersion of Carbon Black in Polyolefin Geosynthetics is the most suitable standard for assessing carbon black dispersion. However, the standard does not enable the dimensions of very small agglomerates to be measured, because the analysis is based upon visual microscopic inspection and subsequent comparison to the referenced micrographs. The International Standard Method ISO 11420: 1996 (E) is used for assessing the degree of carbon-black dispersion in polyolefin pipes, fittings, and compounds in which a carbon-black content of less than 3% is needed. Knowledge about carbon black dispersion and agglomerate sizes can be a significant way of assessing the final product's homogeneity. The assessment must be based upon more than just a visual comparison to a reference chart, as it is in the ASTM D 5596 method. Potential human error in such an approach could be costly for the environment, based on both short- and long-term geomembrane behavior. The ASTM D 5596 method could be modified by applying some elements of the ISO method. Most importantly, the dimensions of all carbon black agglomerates should be counted in the modified method, using a grading chart similar to the one proposed in the ISO 11420 method. Guidelines for a new ASTM procedure are proposed.

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  • Corporate Authors:

    Industrial Fabrics Association International

    345 Cedar Building, Suite 450
    St Paul, MN  United States  55101-1088
  • Authors:
    • Sarazin, P
    • Mlynarek, J
  • Publication Date: 1999-9

Language

  • English

Media Info

  • Features: Photos; References; Tables;
  • Pagination: p. 16-19
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00798416
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Sep 14 2000 12:00AM