| 摘要 |
PURPOSE:To obtain the title resin excellent in heat resistance and transparency, free of optical anisotropy and useful as a material for optical instruments and devices, by reacting a specified dihydric phenol compound with a carbonate- forming compound. CONSTITUTION:A dihydric phenol compound containing a bisphenol A skeleton of formula I (wherein R1 is H or a 1-5 C alkyl, and R2 is a 1-5 C alkyl or phenyl), or a mixture containing at least two such compounds at an arbitrary ratio is directly reacted with a carbonate-forming compound such as phosgene in the presence of an acid binder such as pyridine or NaOH and a solvent such as methylene chloride or xylene and, optionally, a catalyst such as a tert. amine or a quat. ammonium salt (e.g., triethylamine) and an MW modifier (e.g., p-t-butylphenol) to obtain the title resin of an intrinsic viscosity >=0.3dl/g, mainly consisting of repeating units of formula II.
|
