Testing the structure of magnetic paints with and without superimposed shear

A. Potanin, Andrei A. Potanin, Suresh M. Shrauti, David W. Arnold, Alan M. Lane, J. Mellema

Research output: Contribution to journalArticleAcademicpeer-review

10 Citations (Scopus)
75 Downloads (Pure)

Abstract

The structure development in dispersions of magnetic barium ferrite particles in cyclohexanone with polyvinylchloride wetting resin was tested by oscillatory rheological measurements and orthogonal superposition of steady and oscillatory shear. The optimum dispersion is achieved at the resin concentration c=c0, which corresponds to a minimum in the viscoelastic modulii. At c<c0 the system is highly elastic, brittle (G′ drops sharply and G′′ goes through a strong maximum at high strain), thixotropic and its relaxation spectrum, H(τ), is dominated by long relaxation times, τ, which indicates the existence of a strong network. At c>c0 the system becomes less elastic, more flexible, less thixotropic and H(τ) is dominated by short τ, which indicates that the structure formation in this case is dominated by small aggregates rather than a network. By superimposing steady and oscillatory shear we show that the steady shear dramatically break the structure and shifts H(τ) to very short τ.
Original languageUndefined
Pages (from-to)1337-1347
Number of pages11
JournalJournal of rheology
Volume41
Issue number6
DOIs
Publication statusPublished - 1997

Keywords

  • METIS-129205
  • IR-73489

Cite this

Potanin, A., Potanin, A. A., Shrauti, S. M., Arnold, D. W., Lane, A. M., & Mellema, J. (1997). Testing the structure of magnetic paints with and without superimposed shear. Journal of rheology, 41(6), 1337-1347. https://doi.org/10.1122/1.550867