Dithionite → Bisphenol A

Participants

Reaction Steps

2371 Parts of deionized water, 156 parts of a 48.5% aqueous sodium hydroxide solution, and 0.6 parts of hydrosulfite were placed in the same apparatus as used in Example 1, and after deoxidation was carried out in the same way as in Example 1, 157.6 parts of bisphenol AF of 99.98% purity and 134.6 parts of bisphenol FL of 99.8% purity were dissolved therein, then 2548 parts of methylene chloride was added, and 98.5 parts of phosgene was blown thereinto at 13° to 16° C. over about 50 min with stirring. Then, 53.2 parts of a 48.5% aqueous sodium hydroxide solution and 8.5 parts of p-tert-butylphenol were added and after they were emulsified by stirring, 0.2 parts of triethylamine was added, followed by stirring at 30° C. for about 2 hours, to complete the reaction. Then the reaction mixture was treated in the same way as in Example 1, to obtain a copolymerized polymer. The specific viscosity of this copolymerized polymer was 0.178, the retention of the specific viscosity after the steam treatment was 85% and the glass transition temperature was 215° C., which show high hydrolysis resistance and high heat resistance, the light transmittance was 89%, which is good, the light transmittance after the heat treatment was 89%, showing excellent heat stability; and the oxidation resistance was remarkably excellent in comparison with the polymer obtained from bisphenol A as shown by curve 3 () in FIG. 2.

Provenance & Evidence