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Date: 21-1-2016
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POLYETHER SULFONES
Polyether sulfones (PES) are another class of engineering thermoplastics generally used for objects that require continuous use of temperatures around 200°C. They can also be used at low temperatures with no change in their physical properties. Polyether sulfones can be prepared by the reaction of the sodium or potassium salt of bisphenol A and 4,4v-dichlorodiphenyl sulfone.
Bisphenol A acts as a nucleophile in the presence of the deactivated aromatic ring of the dichlorophenylsulfone. The reaction may also be catalyzed with Friedel-Crafts catalysts; the dichlorophenyl sulfone acts as an electrophile:
Polyether sulfones could also be prepared using one monomer:
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10 دقائق قبل النوم.. هذا الأسلوب يساهم في تحسين يومك
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الأسباب الشائعة لتفريغ شحن البطارية
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العتبة العباسية تستقبل أكثر من 1000 مواطنٍ لبنانيّ من ضيوف العراق
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