Process for production of stabilized polycarbonate
AssigneeTeijin Limited
InventorsMasumi Hirata, Wataru Funakoshi, Katsushi Sasaki
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Abstract
A process for the production of a stabilized polycarbonate which comprises melt-polycondensing an aromatic dihydroxy compound and a carbonic acid diester in the presence of a polycondensation catalyst and then, after the reaction mixture shows an intrinsic viscosity of at least 0.1, adding at least one stabilizer selected from the group consisting of specific compounds having a sulfonates group sulfonic acid anhydride group or a sulfate group in an amount of 0.01 to 500 ppm of a polycarbonate to be formed, to form a polycarbonate having a desired intrinsic viscosity.
Claims16
A process for producing a stabilized polycarbonate which comprises:
- melt-polycondensing an aromatic dihydroxy compound and a carbonic acid diester in the presence of a polycondensation catalyst to obtain a reaction mixture;
- and
- after the reaction mixture has an intrinsic viscosity of at least 0.1, adding at least one stabilizer in an amount of 0.01 to 300 ppm of the polycarbonate to be formed, said stabilizer selected from the group consisting of compounds having the formula (I)
- A.sup.1 --(Y.sup.1 --SO.sub.3 X.sup.1).sub.m (I)
- wherein A.sup.1 is a hydrocarbon group having a valence of m, which may be substituted,
- Y.sup.1 is a single bond or an oxygen atom,
- X.sup.l is a secondary alkyl group, a tertiary alkyl group, an ammonium cation having the formula (I-a) ##STR43## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently a hydrogen atom or a monovalent hydrocarbon group, or a phosphonium cation having the formula (I-b) ##STR44## wherein each of R.sup.5, R.sup.6, R.sup.7 and R.sup.8 is independently a hydrogen atom or a monovalent hydrocarbon group, and
- m is an integer of 1 to 4, to produce the stabilized polycarbonate.
Dependencies are inferred from the claim text.