Chemistry Reference
In-Depth Information
FIGURE 13.10
The relation between experimental
l
st
and calculated according to the Eq.
T
st
(13.11)
l
values of stable crack critical length for PASF film samples [1].
The value g
L
with the Eqs. (1.9) and (13.14) appreciation can be deter-
mined as follows [4]:
d
g
≈
0, 37
f
.
(13.15)
L
3
-
d
f
As oriented polymers studies showed [20], for them the value n at draw-
ing ratio growth reached the magnitude ~0.425 very fast and further remains
practically constant. Therefore, calculation with the Eq. (13.14) using gives
the value g
or
≈ 7.03. Thus, the theoretical estimation of film samples fracture
stress s
f
can be fulfilled as follows [21]:
0,1
E
K
g
s
=
0L
(13.16)
f
g
s
or
The value
E
o
for PASF was accepted equal to 8.2 GPa [17].
In
Fig. 13.11
,
the comparison of experimental and calculated according
to the Eq. (13.16) polymer films fracture stress values is adduced, which
shows a good correspondence of theory and experiment.
