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Table 11.6 Mechanical Properties of Biaxially Stretched PEN and PET
Films [62]
50 μ Films PEN
a
PET
a
PEN
b
PET
b
Young’s Modulus (MPa) 5000 3800 5350 4200
Tensile Strength (MPa) 265 190 150 110
Stress at 5% Elongation (MPa) 80 140 70 100
Elongation at Break (%) 80 140 70 100
Thermal Shrinkage at 150
◦
C(%) 0.6 1.3 0.4 1.3
a
Machine direction (MD).
b
Transverse direction (TD).
However, in the case of aging of PET and PEN
under moderately accelerated conditions differences
have been observed [64]. The degradation of PET is
largely influenced by the aging environment and the
temperature. The dominant degradation mechanism
changes with the temperature ...