TA Instruments RSA-G2, Руководство пользователя

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Frequency Sweep
Time
In this test, the temperature and strain are held constant and the frequency is varied. The left figure illustrates a viscoelastic
fingerprint for a linear homopolymer and shows the variation of E' and E" as a function of frequency. As frequency is the
inverse of time, the curve shows the time-dependent mechanical response, with short times corresponding to solid-like
behavior and long times to liquid-like behavior.The magnitude and shape of the E' (G') and E" (G") curves depend on the
molecular structure. Frequency sweeps are typically run over a limited range of 0.1 to 100 Hz as shown below on the right for
a pressure sensitive adhesive at 70°C using the RSA-G2 shear sandwich clamp. At this temperature and frequency range,
the sample is in the terminal and plateau regions.
r-..
loll
0
0...
'--"
en
:J
'3
109
'D
0
�
en
en
ld
.9
r-..
0
0...
'--"
en
1 05
:J
'3
'D
0
E
103
(j)
0'>
Q
.Q
101
C/)
10.2
Homopolymer Viscoelastic Fingerprint
Terminal
Region
Extended
range
wins
10°
Rubbery Transition Glassy
Plateau
Region
Region
Region
.......... 1
- -
... I
Extended
rang e
wins
102 104
106 108 1010
Frequency
(Hz)
Testing Modes and Applications
19
Frequency Sweep on PSA
r-..
106
0
0...
'--"
en
:J
Terminal Region
'3
'D
0
�
en
105
en
.9
r-..
Plateau Region
0
0...
'--"
en
:J
'3
'D
104
0
E
(j)
Temperature:
70
0 C
0'>
Strain: 2%
Q
.Q
Shear Sandwich
C/)
103
0.1 1 10
100
Frequency
(Hz)