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Hence, the analogy in behavior of reinforcement degree of polyarylate
by nanoclusters and nanocomposite epoxy polymer/Na
+
-montmorillonite
by layered silicate gives another reason for the consideration of polymer as
natural nanocomposite. Again strong influence of interfacial (intercompo-
nent) adhesion level on nanocomposites of any class reinforcement degree
is confirmed [17].
15.5 THE METHODS OF NATURAL NANOCOMPOSITES
NANOSTRUCTURE REGULATION
As it has been noted above, at present it is generally acknowledged [2],
that macromolecular formations and polymer systems are always natural
nanostructural systems in virtue of their structure features. In this connec-
tion the question of using this feature for polymeric materials properties and
operating characteristics improvement arises. It is obvious enough that for
structure-properties relationships receiving the quantitative nanostructural
model of the indicated materials is necessary. It is also obvious that if the de-
pendence of specific property on material structure state is unequivocal, then
there will be quite sufficient modes to achieve this state. The cluster model
of such state [3-5] is the most suitable for polymers amorphous state struc-
ture description. It has been shown, that this model basic structural element
(cluster) is nanoparticles (nanocluster) (see
Section 15.1
).
The cluster model
was used successfully for cross-linked polymers structure and properties de-
scription [61]. Therefore, the authors of Ref. [62] fulfilled nanostructures
regulation modes and of the latter influence on rarely cross-linked epoxy
polymer properties study within the frameworks of the indicated model.
In Ref. [62], the studied object was an epoxy polymer on the basis of res-
in UP5-181, cured by iso-methyltetrahydrophthalic anhydride in the ratio by
mass 1:0.56. Testing specimens were obtained by the hydrostatic extrusion
method. The indicated method choice is due to the fact, that high hydrostatic
pressure imposition in deformation process prevents the defects formation
and growth, resulting to the material failure [64]. The extrusion strain e
e
was
calculated according to the Eqs. (14.10) and (4.39) and makes up 0.14, 0.25,
0.36, 0.43 and 0.52. The obtained by hydrostatic extrusion specimens were
annealed at maximum temperature 353 K during 15 min.
