Chemistry Reference
In-Depth Information
diamine. In 2010, SABIC (Saudi Basic Industries Corp., the purchaser of GE
Plastics in 2007) opened a 5,000 metric ton per year Ultem
®
plant in Spain.
SABIC also manufactures Ultem in Mt. Vernon IN and this new facility [26]
increases their capacity by 35%.
O
O
NH
2
O
O
O
NH
2
m-phenylene diamine
O
O
O
BPA dianhydride
O
O
N
N
O
O
O
O
x
Ultem
For specific applications, various specialty polyimides have been prepared.
For example, polyimidesiloxanes are useful for screen printing a paste for
microelectronic applications [27].
O
O
O
O
N
N
Si
Si
m
O
O
x
8.9 FLUOROPOLYMERS
Fluoropolymers have excellent heat, chemical and corrosion resistance. The
most common is polytetrafluoroethylene (PTFE), often known by the Dupont
trademark, Teflon®.
®
. Other tradenames include Dyneon
®
(3M) and Fluon
®
(Asahi Glass). The invention of PTFE is often used as an example of serendip-
ity, but it was actually a combination of serendipity, curiosity, and hard work.
Roy Plunkett was working on experimental refrigerants when a cylinder that
had been filled with tetrafluoroethylene (TFE) gas did not deliver gas when the
valve was opened. Often, when something does not occur as planned, people
discard the results and move on, but Plunkett was curious. When the cylinder
was cut open, a white lubricious solid was discovered. Further investigation
revealed the solid to be a polymer of tetrafluoroethylene [28].
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