The limiting viscosity number was found by the extrapolation of Mark-Houwink's relationship between the intrinsic viscosity and the concentration of chitosan in the investigated solution to concentration of chitosan of zero.
where Mv is the viscosity average molar mass, [[eta].sub.L] is limiting viscosity number, and K and a are Mark-Houwink constants.
Greek Letters [[eta].sub.i]: Intrinsic viscosity [dm.sup.3] [g.sup.-1] [[eta].sub.L]: Limiting viscosity number [dm.sup.3] [g.sup.-1].
It begins with the measurement of dilute solution viscosity, including the limiting viscosity number (intrinsic viscosity) and related parameters.
A key viscosity parameter for polymer characterization is the limiting viscosity number or intrinsic viscosity, [[eta]].
The viscosity number and logarithmic viscosity number vary with concentration, but each can be extrapolated (Figure 2) to zero concentration to give the limiting viscosity number (intrinsic viscosity).