Table 3 The examples of systems for the preparation of noncovalent (physical) cryogels
Polymeric precursor (its
concentration in the
feed)
Solvent
Conditions of cryotropic gel formation
What was done and reported References
Freezing
temperature
Frozen
storage
duration
Thawing
rate
Number of freeze–
thaw cycles
(
C)
(h)
(
C/min)
I. Polysaccharides
Agar-agar (0.25–1.0
wt%)
Water
À10
24
~0.2
1
Sponge-like cryogels with a
rather brittle macropore
walls were obtained
[30, 91]
Agarose (2–3 wt%)
Aqueous solutions of
different pH
values
À5 to
À30
23
~0.3
1
Preparation of agarosebased cryogels, study of
their physicochemical
properties and peculiarities of the wide pore
structure
[270–272]
Amylopectin
Water or 0.35 M
NaCl solution
À6 to
À24
18
3.00;
0.30;
0.03
1
Preparation of polysaccharide cryogels, study of
the influence of cryogenic process regimes on
the properties of final
cryogels, demonstration
of synergism of the
amylopectin and amylose interactions upon
the gel formation
[268]
Amylopectin + amylose
(0.5–2 g/dL)
18
[74]
Carboxy-methylated
curdlan (0.5–3 wt%)
Acidified water
(pH 0.76–2.40)
À18
24–48
À
1–5
Preparation of the CMcurdlan-based cryogels,
study of their swelling
behavior and of the
nature of interchain
linking
[279]
24
V.I. Lozinsky