Page 262 - Engineering Plastics Handbook
P. 262
224 Engineering Plastics
■ The effect of the amino-substituted position of the etherdiamine
■ Number of benzene rings in ether diamine (Table 10.2)
■ Amino substituted position in ether diamine
■ Optimum molecular weight
These factors affect the thermoplasticity of polyimides. Then it was con-
cluded that
1. Thermoplasticity can be controlled through the selection of ether
diamine with a specific chain length.
2. Polyimide from meta amino substituted diamine has less heat resist-
ance than polyimide from the para form. The polymer of the meta
form, however, has much better plasticity than that of the para form,
and T .
in light of T g m
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Aurum has a chemical structure consisting of repeating units of
pyromellitic dianhydride and 4,4′-bis(3-aminophenoxy)biphenyl, with T g
= 482°F (250°C) and T = 734°F (390°C).
m
Products and Design
Applications Using Mitsui Chemicals
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Aurum TPI
There are five major categories for the applications:
1. Electronics, electrical, and semiconductor
2. Automotive
3. Industrial (including business machinery)
4. Wire, cable, film, and fiber
5. Aircraft and aerospace
The heat resistance has helped applications in various parts that need
high-temperature resistance, up to 455°F (235°C).
Moreover, the dimensional stability based on high heat resistance
has increased applications requiring tight tolerances of the parts. The
superior wear and friction properties of polyimide have fascinated many
engineers who had to design parts used under harsh conditions. This is
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so because many kinds of parts made with Aurum have been com-
mercialized.
Electronics, electrical, and semiconductor. The excellent dielectric prop-
erties and resistance to heat and abrasion that characterize Aurum ®