| 摘要 |
PURPOSE:To obtain the titled polycarbonate of high glass transition temperature, good in film-forming capability, suitable for mechanical and electrical applications, by polycondensation between specific pyrazine and a polycarbonate oligomer, a reaction product from specific propane compound and phosgene. CONSTITUTION:The objective polycarbonate having recurring units of formulae I and II, or formulae III and IV, respectively, can be obtained by polycondensation between (A) 2,5-bis(p-hydroxyphenyl)pyrazine and (B) a polycarbonate oligomer with chloroformate groups at the both ends prepared by reaction between (i) 2,2-bis(4'-hydroxyphenyl)propane and (ii) phosgene.
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