Provided are a polycarbonate-polyorganosiloxane copolymer having a carbon tetrachloride concentration of less than 4 ppm by mass, and the following production method for producing the polycarbonate-polyorganosiloxane copolymer. More specifically, provided is a method of continuously producing a polycarbonate-polyorganosiloxane copolymer, the method comprising the steps of: (A) continuously or intermittently taking a polymerization reaction liquid, which is obtained by polymerizing a dihydric phenol compound, a carbonate precursor, and a specific polyorganosiloxane in the presence of an alkaline compound aqueous solution and a water-insoluble organic solvent, out of a reactor; (B) separating the polymerization reaction liquid taken out in the step (A) into an aqueous phase and a water-insoluble organic solvent phase; (C) washing the water-insoluble organic solvent phase separated in the step (B), followed by separation thereof into an aqueous phase and a water-insoluble organic solvent phase; (D) concentrating the water-insoluble organic solvent phase separated in the step (C); and (E) recovering part or all of the water-insoluble organic solvent removed by evaporation in the step (D), followed by distillation purification thereof in a distillation column, the water-insoluble organic solvent obtained in the step (E) being reused as at least part of the water-insoluble organic solvent in the step (A) or as an extraction solvent for the aqueous phase separated in the step (B), or as both thereof, in the step (E), the distillation purification being performed while a concentration of the polycarbonate-polyorganosiloxane copolymer in a column bottom liquid of the distillation column is controlled to 6% by mass or less.

The present invention relates to polysiloxane-polycarbonate block cocondensates comprising particular rearrangement structures and having improved rheological properties and melt stability as well as to mouldings and extrudates made from these polysiloxane-polycarbonate block cocondensates.

The present invention relates to polysiloxane-polycarbonate block cocondensates comprising particular rearrangement structures and having improved rheological properties and melt stability as well as to mouldings and extrudates made from these polysiloxane-polycarbonate block cocondensates.

The present invention relates to a process for preparing polysiloxane-polycarbonate block cocondensates proceeding from specific polycarbonates and hydroxyaryl-terminated polysiloxanes.

The present invention relates to a process for preparing polysiloxane-polycarbonate block cocondensates proceeding from specific polycarbonates and hydroxyaryl-terminated polysiloxanes.

A thermoplastic composition including a polycarbonatesiloxane-arylate; a phthalone compound; and optionally an additional component different from the polycarbonatesiloxane-arylate and the phthalone compound; wherein the phthalone compound has a formula: wherein Z.sub.1 represents the atoms necessary to complete a 9- to 13-membered single or fused aromatic ring structure, Z.sub.2 represents the atoms necessary to complete a pyridine or quinoline ring, each R.sub.1 and each R.sub.2 are independently halogen, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, an aromatic or aliphatic thioether group, an aromatic or aliphatic carboxylic acid ester group, or an aromatic or aliphatic amide group, a is an integer from 0 to 6, b is an integer from 0 to 4, n is 1 or 2, and X is present only if n=2 and is a single bond or a divalent organic radical bonded to the Z.sub.1 ring structure through an ether, ketone, or thio linkage.

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A method of producing a polycarbonate, including: introducing a tertiary amine into a reaction process; and performing interfacial polycondensation between an alkali aqueous solution of a dihydric phenol and phosgene in the presence of an organic solvent, in which: (i) a portion into which the tertiary amine is introduced comprises at least a tertiary amine storage tank, a tertiary amine supply pipe, and a diluent solvent supply pipe; (ii) the portion further includes a pressure control valve in the tertiary amine supply pipe on an upstream side of a merging portion with the diluent solvent supply pipe; and (iii) when a pressure P.sub.1 of an inside of the tertiary amine storage tank pressurized by a pressurization gas and a pressure P.sub.2 in a portion ranging from an outlet of the storage tank to an upstream side of the pressure control valve, a relationship of P.sub.1≦P.sub.2 is satisfied.

A method of producing a polycarbonate, including: introducing a tertiary amine into a reaction process; and performing interfacial polycondensation between an alkali aqueous solution of a dihydric phenol and phosgene in the presence of an organic solvent, in which: (i) a portion into which the tertiary amine is introduced comprises at least a tertiary amine storage tank, a tertiary amine supply pipe, and a diluent solvent supply pipe; (ii) the portion further includes a pressure control valve in the tertiary amine supply pipe on an upstream side of a merging portion with the diluent solvent supply pipe; and (iii) when a pressure P.sub.1 of an inside of the tertiary amine storage tank pressurized by a pressurization gas and a pressure P.sub.2 in a portion ranging from an outlet of the storage tank to an upstream side of the pressure control valve, a relationship of P.sub.1≦P.sub.2 is satisfied.

The present invention relates to a process for preparing polysiloxane-polycarbonate block cocondensates proceeding from specific polycarbonates and hydroxyaryl-terminated polysiloxanes in presence of a salt of a weak acid.

The present invention relates to a process for preparing polysiloxane-polycarbonate block cocondensates proceeding from specific polycarbonates and hydroxyaryl-terminated polysiloxanes in presence of a salt of a weak acid.