Biomedical Engineering Reference
In-Depth Information
Table 9.12 The effect of aging on SC characteristics of polymer-ceramic
nanocomposites with Mn, Co, Zn and Ni
Metal-monomer
complex
Pressing
duration
(min)
Y
1
Ba
2
Cu
3
O
6.98
Metal
T
c
/
T
c
(K)
T
f
/
T
f
(K)
Mass (g) Mass (%) Mass (g) Mass (%)
0.293
43
0.388
57
Mn
10
95/96
87/89
0.396
50
0.396
50
Mn
5
94/96
85/87
0.90
70
0.29
30
Mn
5
94/95
84/88
0.518
73
0.196
27
Mn
5
93/96
85/90
0.90
70
0.39
30
Mn
5
95/96
85/91
0.416
67
0.209
33
Mn
10
94/96
83/86
0.552
78
0.156
22
Mn
5
95/96
85/88
0.325
51
0.318
49
Co
5
93/95
83/85
0.432
60
0.283
40
Co
5
92/9
84/89
0.503
70
0.228
30
Co
2
92/95
84/87
0.486
70
0.208
30
Ni
5
95/96
83/85
of composite products evolving upon destruction of the matrix). The
possible participation of oxygen, produced by the ceramic during the
orthorhombic phase of thermo-oxidative destruction of matrix condi-
tions, may broaden the temperature interval of the SC transition.
On the basis of data obtained on the nature of the change of physical-
mechanical and SC properties of high-temperature SC nanocomposites,
dependent on granulometric composition and filling degree, it can be
concluded that certain key factors play a significant role. These factors
include the peculiarities of forming the boundary of the interstitial layer, the
role of the oxide and the highly conductive ceramic-binder, its structure,
and the adhesion of the binder with the surface of the ceramic. For the
nanocomposites considered here, an increase in melting temperature was
found. This can be explained by the intercalation of macromolecule
fragments into the interstitial layer of the ceramic grains. This phenomenon
leads to a change in the morphological structure of the SC nanocomposites
obtained, as has been proven by electron microscopy.
The ceramic-binder boundary plays an important role in the SC and
mechanical properties of SC polymer-ceramic nanocomposites based on
SHMPE. According to data on dynamic-mechanical properties obtained
over a wide temperature interval, it can be concluded that the peculiarities of
the formation of the interface within the ceramic-binder boundary are the
most important factor. Data on electron microscopy and EPR signals on
Cu
2+
(I) are sound proof of the presence of intercalated fragments of the
macromolecules in the interlayer space of the ceramic grains, leading to the
formation of nanostructures.
The activation of Y
1
Ba
2
Cu
3
O
6.97
on the surface of the ceramic grains
