Polysulphones are amorphous engineering thermoplastics containing
the sulfone groups (SO2)
in the main chain along with a variety of aromatic
constituents like ether or iso-propylidene groups.
There are four major members of the polysulfone
family. These are:
1) Polysulfone
2) Polyarylsulfone
3) Polyethersulfone
4) Polyphenylsulfone
Properties:
Polysulphones are engineering plastics with
high strength, stiffness combined with toughness.
They display high thermal and oxidative stability,
low creep and transparency - The presence of
aromatic elements and sulfone group provide
resistance to heat and oxidation.
They display good dimensional stability, retain
strength and dielectric properties during their
service life.
Polysulfones have low flammability.
Very few polymers can match this high temperature
performance - Polysulfone can be used upto 150
degree C, whereas Polyethersulfone can be used
upto 200 degree C.
Resistance to hydrolysis at high temperature
and to most acids, alkalies and non polar organic
solvents is excellent, but the resin may however
be attacked or dissolved by polar solvesnts,
especially under stress.
Resistance to ionization radiation is high,
however protection to UV radiation is needed
for outdoor applications.
Applications:
Polysulfones find application in electronic
and automotive parts, fiber optics, medical
instruments requiring sterilization, chemical
and food processing equipment, plumbing and
home appliance items etc.
Copolymers of Polysulfones have potential in
medical application to be used as an artificial
membrane to remove CO2 and
perfuse with O2. Membranes
are semi-permeable barriers that allow certain
substances such as water to pass through, while
other substances like bacteria and viruses are
selectively separated and not allowed to pass
through. Other applications of Polysulfone membranes
include water purification (both potable and
waste), medical filtration, and gas separation,
as well as a variety of industrial filtration.
(Ref:- A Brydson, D. N. Gray,
McGraw-Hill, Solvay)
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