intensive peaks at the high temperatures (720 – 743 K), which relate to the thermal
decomposition of materials, are observed on the DTA curves in this area.
When copper and bronze are present there is an earlier start of thermal
decomposition: the temperature of the start of intensive decomposition of phenylone
moves toward lower temperatures (by 5 – 20 K). Also, the speed of thermal
decomposition process of polymer matrix increases by 10 – 20%. Herewith, maximums
of the decomposition speed of polymer are moved according to the temperature scale
to the lower temperature ranges (by 9 – 20 K) relatively to the same maximum of the
unfilled phenylone. Respectively, the heat resistance of MPs based on the phenylone
and copper or bronze decreases by 9 – 32 K too, progressing with an increase in content
of FM as it’s showed in the work [21].
In contradiction to copper and bronze, other metal FMs don’t accelerate the
process of thermal decomposition of phenylone. The temperature of the beginning of
decomposition of metal-containing polymers based on phenylone and titanium is
comparable to the same one for unfilled polymer. And the temperature even raises for
phenylone with aluminum or nickel powder. At the same time the speed of
decomposition process of polymer matrix decreases by 12 – 20%. It’s worth nothing
that the exothermic peaks for the MPs containing Al, Ti and Ni, and the same way for
metal-containing polymers which include Cu and Br, are shifted by several degrees in
the area of lower temperatures in comparison with unfilled polymer.
So, the process of thermal decomposition of polymer matrix is intensified in the
presence of powdery copper and bronze, and in the presence of titanium, aluminum
and nickel it is inhibited (see Table 5). For example, if the mass loss of unfilled
phenylone after the heat up to 773 K is 36.4 wt.%, then of MPs with copper or bronze
it’s by 9 – 13 % higher, and of MPs with titanium, aluminum or nickel – by 9 – 14 %
lower.
Table 5 The impact of disperse metal fillers on the thermal decomposition of
aromatic polyamide
The loss of mass of polyamide, with heating to 773 K, containing 15 wt.% of filler:
APP
Bronze
Cu
Ti
Al
Ni
36.4
41.0
39.7
33.1
32.63
31.3
Proceeding from the above, it is possible to conclude that thermochemical
transformations of phenylone filled with copper and bronze go a little differently
comparing to the transformation process of MPs with titanium, aluminum and nickel.
It can be connected, from the one hand, with more active impact of the disperse copper
or bronze on the process of composite structuring at the formation of MPs in the
conditions of increased temperatures and pressures. This is indicated by the changes in
IR absorption spectrums as it is showed in the work [22]. The appearance of new
absorption bands can indicate a difficult physic-chemical interaction of active centers
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