Dispersion of Modified Fumed Silica in Elastomeric Nanocomposites

Details

• Personal Author:
  Beaucage G ; Chauby M ; Grammens J ; Kammler HK ; Kuppa VK ; McGlasson A ; Narayanan V ; Okoli U ; Rishi K
• Description:
  In polymer nanocomposites, surface modification of silica aggregates can shield Coulombic interactions that inhibit agglomeration and formation of a network of agglomerates. Surface modification is usually achieved with silane coupling agents although carbon-coating during pyrolytic silica production is also possible. Pyrogenic silica with varying surface carbon contents were dispersed in styrene-butadiene (SBR) rubber to explore the impact on hierarchical dispersion, the emergence of meso-scale structures, and the rheological response. Pristine pyrogenic silica aggregates at concentrations above a critical value (related to the Debye screening length) display correlated meso-scale structures and poor filler network formation in rubber nanocomposites due to the presence of silanol groups on the surface. In the present study, flame synthesized silica with sufficient surface carbon monolayers can mitigate the charge repulsion thereby impacting network structural emergence. The impact of the surface carbon on the van der Waals enthalpic attraction, a*, is determined. The van der Waals model for polymer nanocomposites is drawn through an analogy between thermal energy, kBT, and the accumulated strain, y. The rheological response of the emergent meso-scale structures depends on the surface density of both carbon and silanol groups. [Description provided by NIOSH]
• Subjects:
  Butadienes Occupational Health Polymers Safety Silicon Dioxide Styrene
• Keywords:
  Carbon Nanocomposites Nanostructures Silica
• ISSN:
  0032-3861
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Massachusetts ; Ohio ; OSHA Region 1 ; OSHA Region 3 ; OSHA Region 5 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  264
• NIOSHTIC Number:
  nn:20066783
• Citation:
  Polymer 2023 Jan; 264:125407
• Contact Point Address:
  Gregory Beaucage, Chemical & Materials Engineering, University of Cincinnati, Cincinnati, OH, 45221, USA
• Email:
  beaucag@uc.edu
• CAS Registry Number:
  Silica (CAS RN 7631-86-9)
• Federal Fiscal Year:
  2023
• Peer Reviewed:
  True
• Source Full Name:
  Polymer
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:715e21ba2d8a386bab0bc904dbbc00d13778695020befe10ddf1c18599bb0bee75c6dba32da81ab78c7a670ea5d093d9bd3fe33dc0f76e797afa26ef274d5c23
• Download URL:
  https://stacks.cdc.gov/view/cdc/231160/cdc_231160_DS1.pdf
• File Type:
  [PDF - 10.00 MB ]