反応 #59225

反応方程式

4,4′-dihydroxydiphenyl ether

phosgene

sodium hydroxide

p-tert.-butylphenol

sodium hydroxide

n-ethylpiperidine

bisphenol A

→

bisphenol A 4,4′-dihydroxydiphenyl ether

溶媒

methylene chloride

water

反応条件

後処理

1. 1
   workup.ADDITIONwas added during the phosgenation
2. 2
   workup.ADDITIONis added as catalyst
3. 3
   その他The aqueous phase is separated off
4. 4
   洗浄washed with distilled water until neutral and free of salt
5. 5
   その他Precipitation of the polymer in methanol
6. 6
   乾燥drying yield 17.29 g of polycarbonate

実験手順

131 ml of methylene chloride are added to a solution, rendered inert with nitrogen, of 1.618 g (0.008 mol.) of 4,4′-dihydroxydiphenyl ether and 16.438 g (0.072 mol.) of bisphenol A as well as 7.04 g (0.176 mol.) of sodium hydroxide in 131 ml of water. In a one-step procedure, 0.36 g (0.0024 mol. or 3.0 mol. % relative to bisphenol) of p-tert.-butylphenol (BUP) are added as chain terminator. At a pH value of 14 and at room temperature, 11 ml (15.8 g, 0.16 mol.) of phosgene are added in the course of 10 minutes. In order to prevent the pH value from falling below 12, 25% sodium hydroxide solution was added during the phosgenation. When the phosgenation is complete, and after rinsing with nitrogen, 0.11 ml (0.0008 mol., 1 mol. % relative to bisphenol) of n-ethylpiperidine is added as catalyst, and stirring is then carried out for one hour. The aqueous phase is separated off, and the organic phase is acidified with phosphoric acid and washed with distilled water until neutral and free of salt. Precipitation of the polymer in methanol and drying yield 17.29 g of polycarbonate.

出典