Idemitsu Kosan Company, Limited

Idemitsu Petrochemical Co., Ltd.

Hiroaki Motegi

Yasuhiro Ishikawa

Yukiko Nagao

Noriyuki Kunishi

Akihiro Shishikura

Masahiro Takahashi

Seiji Takahashi

Masayuki Takahashi

Kenji Sasaki

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 Pof an inside of the tertiary amine storage tank pressurized by a pressurization gas and a pressure Pin a portion ranging from an outlet of the storage tank to an upstream side of the pressure control valve, a relationship of P&#x2264;Pis satisfied.

Process for producing polycarbonate

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.

Polycarbonate-polyorganosiloxane copolymer and method for continuously producing same

Provided is a method for economically and stably producing a high-quality polycarbonate-polyorganosiloxane copolymer excellent in, for example, transparency and impact resistance in a continuous manner. Specifically, provided is a method of continuously producing a polycarbonate-polyorganosiloxane copolymer, the method including a step (A) of continuously or intermittently taking a polymerization reaction liquid, which is obtained by polymerizing a dihydric phenol-based compound, a carbonate precursor, and a polyorganosiloxane in the presence of an alkaline compound aqueous solution and a water-insoluble organic solvent, out of a reactor, the step (A) including the following step (a-1) and the following step (a-2), the method using a dissolution tank for dissolving the dihydric phenol-based compound in the alkaline compound aqueous solution to prepare an alkaline compound aqueous solution of the dihydric phenol-based compound to be used in each of both the step (a-1) and the step (a-2), the step (a-2) including, before mixing a polycarbonate oligomer and the dihydric phenol-based compound, mixing the alkaline compound aqueous solution and the alkaline compound aqueous solution of the dihydric phenol-based compound prepared in the dissolution tank: step (a-1): a step of mixing the alkaline compound aqueous solution of the dihydric phenol-based compound prepared in the dissolution tank and the polycarbonate precursor, followed by a reaction of the mixture in the presence of the water-insoluble organic solvent to produce the polycarbonate oligomer; and step (a-2): a step of continuously or intermittently taking the polymerization reaction liquid, which is obtained by mixing the alkaline compound aqueous solution of the dihydric phenol-based compound prepared in the dissolution tank, the polycarbonate oligomer obtained in the step (a-1), and the polyorganosiloxane, and polymerizing the mixture in the presence of the water-insoluble organic solvent, out of the reactor.

Method for continuous production of polycarbonate-polyorganosiloxane copolymer

The present invention provides a method for producing a polycarbonate-polyorganosiloxane copolymer economically and stably, in particular, the present invention is concerned with a method for continuous production of a polycarbonate-polyorganosiloxane copolymer including (A) a step of withdrawing a polymerization reaction solution obtained by polymerizing a dihydric phenol compound, a carbonate precursor, and a polyorganosiloxane in the presence of an alkaline compound aqueous solution and a water-insoluble organic solvent continuously or intermittently from a reactor; (B) a step of separating the polymerization reaction solution withdrawn in the step (A) into an aqueous phase and a water-insoluble organic solvent phase; and (C) a step of after washing the water-insoluble organic solvent phase separated in the step (B) with an acidic aqueous solution, separating the resultant into an aqueous phase and a water-insoluble organic solvent phase, wherein the content of the polycarbonate-polyorganosiloxane copolymer in the aqueous phase separated in the step (C) is controlled to not more than 2% by mass, and a part or the whole of an extract obtained by extracting the aqueous phase separated in the step (C) with a water-insoluble organic solvent is reused for the step (A).

Provided is a polycarbonate-polyorganosiloxane copolymer having high impact resistance and excellent transparency, in particular, a high total light transmittance and a small haze, and a method of producing thereof. Specifically, provided is a polycarbonate-polyorganosiloxane copolymer, containing a main chain having a repeating unit represented by the following general formula (I) and a constituent unit represented by the following general formula (II), in which: n in the general formula (II) is 25 to 50; and the copolymer satisfies the following conditions (a) and (b): (a) a molded article having a thickness of 2 mm made of the copolymer has a total light transmittance measured based on ISO 13468 of 88% or more and a haze measured based on ISO 14782 of 0.7% or less; and (b) a molded article having a thickness of 3 mm made of the copolymer has a total light transmittance measured based on ISO 13468 of 88% or more and a haze measured based on ISO 14782 of 1.0% or less. (In the formulae, Rand Reach independently represent a halogen atom, an alkyl group or an alkoxy group, X represents a single bond, an alkylene group, an alkylidene group, a cycloalkylene group, a cycloalkylidene group, &#x2014;S&#x2014;, &#x2014;SO&#x2014;, &#x2014;SO&#x2014;, &#x2014;O&#x2014; or &#x2014;CO&#x2014;, and a and b each independently represent an integer of 0 to 4. Rto Reach independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an aryl group, Y represents a single bond, or an organic residue containing an aliphatic or aromatic moiety, and n represents an average repetition number.)

Polycarbonate-polyorganosiloxane copolymer and method for producing same

The present invention provides a method for producing a polycarbonate-polyorganosiloxane copolymer economically and stably, in particular, the present invention is concerned with a method for continuous production of a polycarbonate-polyorganosiloxane copolymer including (A) a step of withdrawing a polymerization reaction solution obtained by polymerizing a dihydric phenol compound, a carbonate precursor, and a polyorganosiloxane in the presence of an alkaline compound aqueous solution and a water-insoluble organic solvent continuously or intermittently from a reactor; (B) a step of separating the polymerization reaction solution withdrawn in the step (A) into an aqueous phase and a water-insoluble organic solvent phase; and (C) a step of after washing the water-insoluble organic solvent phase separated in the step (B) with an acidic aqueous solution, separating the resultant into an aqueous phase and a water-insoluble organic solvent phase, wherein the aqueous phase separated in the step (C) is extracted with a water-insoluble organic solvent, the content of the polycarbonate-polyorganosiloxane copolymer in the obtained extract is controlled to not more than 2% by mass, and a part or the whole of the extract is reused for the step (A).

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Ichihara, Japan

Hiroaki Motegi