Sedimentation

It isn't known for certain that this is THE Svedberg Equation This equation has the Svedberg constant, s, in it, and it gives molecular weight too.

(Hiementz-638)
weight average fractions.
  • There is no reference in Sperling to sedimentation.

  • [Hiementz-635] starts a discussion with lots of equations.

  • [Hiementz-640] states that this method is used for biological protein solutions which may be comprised of a few polymers of distinctly different molecular weights.

  • [Hiementz-641 states that the general problems become more severe when you use synthetic polymers.

    • Polydisperse samples are more prone to give you the problem of uncertainty of determining what type of molecular weight you are determining.

    • The difference in the refractive indices of the polymer and the solvent must be significant, and this may be more difficult because for synthetic polymers of significant weight, the organic solvent that dissolves the organic polymer may not differ that significantly with regard to refractive index.


    Last Update- September 1, 1995- wld