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Hence, the authors of Ref. [73] considered the multifractal concept of
amorphous glassy polymers yielding process. It is based on the hypothesis,
that the yielding process presents itself structural transition from multifractal
to regular fractal. In a amorphous glassy polymers Shennone informational
entropy to an approximation of constant coincides with entropy, which is
due to polymer fluctuation free volume change. The approximate quantita-
tive estimations confirm the offered hypothesis correctness. The postulate
about yielding process realization possibility only for polymers fractal struc-
ture, presented as a physical fractal within the definite range of linear scales,
is the main key conclusion from the stated above results. What is more, the
fulfilled estimations strengthen this definition - yielding is possible for poly-
mer multifractal structure only and represents itself the structural transition
multifractal - regular fractal [73].
FIGURE 4.21
The temperature dependences of correlation
d
c
(1), informational
d
I
(2) and
Hausdorff
d
f
(3) dimensions of PC multifractal structure [73].
Let us consider in the present chapter conclusion the treatment of depen-
dences of yield stress on strain rate and crystalline phase structure for semi-
crystalline polymers [77]. As it known [91], the clusters relative fraction j
cl
is an order parameter of polymers structure in strict physical significance of
this term and since the local order was postulated as having thermofluctua-
tion origin, then j
cl
should be a function of testing temporal scale in virtue of
