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Epoxy resins are one of
the most important types of reactive glues. By changing the
curing agents and/or conditions of curing, the rate of
reaction is influenced.
For technical applications, the real curing behavior for
certain conditions is a point of interest. Therefore, the
kinetics of the curing reaction is often investigated on the
basis of commercial products.
It is well known that only on the basis of several
measurements, performed at different heating rates and/or
different temperatures, the predictions exhibit a sufficient
level of confidence. Therefore in this example 3 dynamic and
3 isothermal measurements are combined.
Measurements
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Instrument:
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NETZSCH
DSC 204 Phoenix
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Heating rates
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of dynamic
measurements:
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0.25, 1, 5 K/min
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Isothermal
temperatures:
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137, 167, 197
¡C
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Sample mass:
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8 .. 12
mg
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Model-free Analysis
Model-Fit

This picture demonstrates
that it is possible to describe simultaneously with a high
fit quality dynamic and isothermal measurements in addition
to using the same kinetic model.
Prediction according to a user-defined temperature
program
After definition of a
temperature program, including heating up, cooling down and
isothermal steps the fractional reaction is calculated,
using the results of kinetic analysis.
Isothermal
Prediction
The fractional reaction -
at DSC by partial area - is calculated for a set of
temperatures and a certain time.
Tabular report of the time for a given degree of
reaction
(Partial Area) Maximum time: 200 min
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Partial
Area/%
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Temperature/¡C
|
|
|
120
|
130
|
140
|
150
|
160
|
170
|
180
|
190
|
|
2
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9.1
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5.4
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3.3
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2.0
|
1.3
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0.8
|
0.5
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0.4
|
|
5
|
21.3
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12.7
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7.8
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4.9
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3.1
|
2.0
|
1.3
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0.9
|
|
10
|
38.3
|
23.2
|
14.4
|
9.1
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5.9
|
3.9
|
2.6
|
1.7
|
|
20
|
65.2
|
40.2
|
25.4
|
16.3
|
10.7
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7.1
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4.8
|
3.3
|
|
30
|
87.2
|
54.5
|
34.8
|
22.6
|
15.0
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10.1
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6.9
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4.8
|
|
40
|
107.5
|
67.8
|
43.7
|
28.6
|
19.1
|
13.0
|
8.9
|
6.2
|
|
50
|
128.1
|
81.4
|
52.8
|
34.9
|
23.5
|
16.0
|
11.1
|
7.8
|
|
60
|
151.0
|
96.6
|
63.1
|
42.0
|
28.4
|
19.5
|
13.6
|
9.7
|
|
70
|
179.4
|
115.5
|
75.9
|
50.8
|
34.6
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23.9
|
16.8
|
12.0
|
|
80
|
|
143.0
|
94.6
|
63.8
|
43.7
|
30.4
|
21.5
|
15.4
|
|
90
|
|
197.8
|
132.0
|
89.7
|
62.0
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43.6
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31.1
|
22.4
|
|
95
|
|
|
181.2
|
124.0
|
86.2
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61.0
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43.7
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31.8
|
|
98
|
|
|
|
190.0
|
133.0
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94.6
|
68.3
|
49.9
|
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