Measuring Particle Size-Dependent Physicochemical Structure in Airborne Single Walled Carbon Nanotube Agglomerates

Details

• Personal Author:
  Emery M ; Ku BK ; Maynard AD ; McMurry PH ; Stolzenburg M
• Description:
  As-produced single-walled carbon nanotube (SWCNT) material is a complex matrix of carbon nanotubes, bundles of nanotubes (nanoropes), non-tubular carbon and metal catalyst nanoparticles. The pulmonary toxicity of material released during manufacture and handling will depend on the partitioning and arrangement of these components within airborne particles. To probe the physicochemical structure of airborne SWCNT aggregates, a new technique was developed and applied to aerosolized as-produced material. Differential Mobility Analysis-classified aggregates were analyzed using an Aerosol Particle Mass Monitor, and a structural parameter Gamma (proportional to the square of particle mobility diameter, divided by APM voltage) derived. Using information on the constituent components of the SWCNT, modal values of Gamma were estimated for specific particle compositions and structures, and compared against measured values. Measured modal values of Gamma for 150 nm mobility diameter aggregates suggested they were primarily composed of non-tubular carbon from one batch of material, and thin nanoropes from a second batch of material - these findings were confirmed using Transmission Electron Microscopy. Measured modal values of Gamma for 31 nm mobility diameter aggregates indicated that they were comprised predominantly of thin carbon nanoropes with associated nanometer-diameter metal catalyst particles; there was no indication that either catalyst particles or non-tubular carbon particles were being preferentially released into the air. These results indicate that the physicochemistry of aerosol particles released while handling as-produced SWCNT may vary significantly by particle size and production batch, and that evaluations of potential health hazards need to account for this. [Description provided by NIOSH]
• Subjects:
  Occupational Health Particulate Matter Safety
• Keywords:
  Mathematical-models Measurement-equipment Nanotechnology Particle-aerodynamics Particle-counters Particulate-sampling-methods Particulates
• ISBN:
  9781402058585
• Publisher:
  Springer
• Document Type:
  Text
• Genre:
  Book
• Place as Subject:
  District of Columbia ; Minnesota ; Ohio ; OSHA Region 3 ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DART - Division of Applied Research and Technology
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  85-92
• NIOSHTIC Number:
  nn:20032627
• Citation:
  Nanotechnology and occupational health. Maynard AD, Pui DYH, eds. Dordrecht, The Netherlands: Springer, 2007 Mar; :85-92
• Contact Point Address:
  A. D. Maynard, Woodrow Wilson Int Ctr Scholars, Project Emerging Nanotechnol, 1 Woodrow Wilson Pl,1300 Penn Ave NW, Washington, DC 20004
• Email:
  andrew.maynard@wilsoncenter.org
• Editor(s):
  Maynard AD; Pui DYH
• Federal Fiscal Year:
  2007
• NORA Priority Area:
  Manufacturing
• Peer Reviewed:
  False
• Source Full Name:
  Nanotechnology and occupational health
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:cbbae89ff8a466a991707923a6214b6ff438bdfbea115e3f4a7d884ef0f9c38e3b2e789d7ebff3ef516cbfc2b500704f695568358b9928418c4ea46407222e78
• Download URL:
  https://stacks.cdc.gov/view/cdc/186531/cdc_186531_DS1.pdf
• File Type:
  [PDF - 1.34 MB ]