Page 28 - Introduction to Colloid and Surface Chemistry

The colloidal state 19

Motor

Colloidal solution
being dialysed
Visking dialysis
tubing

Figure 1.5 A simple dialysis set-up

index of the emerging solution, and the relationship between
retention time and relative molecular mass is determined by
calibrating the apparatus with polymer fractions which have been
characterised by other methods, such as osmotic pressure (see page
37), light scattering (see page 57) or viscosity (see page 251).
A further modification of dialysis is the technique of electrodialysis,
as illustrated in Figure 1.6, The applied potential between the metal

W i
_J L \
==•===•"=£1= = r~ — - - —f—
—
i
F" 1 " 1 "' — — . . r-__j_L._,
— Solvent - 5 -solution ErH 1 1— Solvent —
-
•4 — i r r ^T'_: _rz_'"ZJ'nz; zi ; 1 1 J*=-
r
: 1

Figure 1.6 Electrodialysis