write the precautions to be taken while peparing the semi permiqble membrane
Answers
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1. A method for the production of semipermeable membranes, which comprises
exposing porous shaped articles of polysulfone having a form of film, sheet, tube or hollow fiber or being composite with another porous support and having pores of 100 to 1000 A in size on the surface thereof, to plasma generated by glow discharge of a gas selected from the group consisting of helium, argon, nitrogen, oxygen, hydrogen, carbon monoxide, carbon dioxide, ammonia, and water under a pressure of 0.01 to 10 Torr to form a dense, crosslinked surface layer of no more than one micron in thickness.
2. A method according to claim 1 wherein said polysulfone has the following recurring units or mixture thereof: ##STR3##.
3. A method according to claim 1, wherein said glow discharge is generated by applying an alternating current or direct current voltage of 0.5 to 50 kV and wattage of 5 to 2500 watt.
4. A method according to claim 1 wherein the duration of exposure to plasma is 1 to 120 minutes.
5. A method according to claim 1 wherein said porous shaped articles are prepared by a casting process.
6. A semipermeable membrane prepared by the method of claim 1.
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Answer:
The semi permeable membrane can be prepared by the use of egg. While preparing the membrane the exact chemical concentration must be used. Eggs must be soaked in dilute hydrogen chloride and the clean syringe must be used.