An object of the present invention is to provide a novel production method of a poly(ester)carbonate. The present invention relates to a production method of a poly(ester)carbonate, including subjecting a diol and a carbonate ester to a transesterification reaction in the presence of a catalyst, wherein the catalyst comprises aluminum or a compound thereof, and a phosphorus compound.

Provided is a polycarbonate-polyorganosiloxane copolymer, including: a polyorganosiloxane block (A-1) including a specific structural unit; and a polycarbonate block (A-2) formed of a specific repeating unit, wherein the polycarbonate-polyorganosiloxane copolymer satisfies the following condition (A) or (B): condition (A): a hexane extraction amount of the polycarbonate-polyorganosiloxane copolymer is 150 ppm or less; and condition (B): average weights of polyorganosiloxane blocks in polycarbonate-polyorganosiloxane copolymers obtained by separating the polycarbonate-polyorganosiloxane copolymer with a gel permeation chromatograph satisfy a specific expression.

Provided is a resin composition that is highly fluid and has good moldability, and that has excellent optical properties. More specifically, provided is a resin composition that contains a thermoplastic resin and a specific compounding agent containing a naphthalene structure and/or a fluorene structure.

The purpose of the present invention is to provide a polyester resin or polyester carbonate resin, which has high refractive index, while achieving an excellent balance between heat resistance and low birefringence. A polyester resin or a polyester carbonate resin, which contains repeating units represented by the following formulae (1) and (2), and wherein the ratio of the repeating unit represented by formula (1) to the repeating unit represented by formula (2) is 15:85 to 85:15. (In formula (1), each of rings Z.sup.1 and Z.sup.2 represents a polycyclic aromatic hydrocarbon group having 9-20 carbon atoms; each of R.sup.1, R.sup.2, R.sup.7 and R.sup.8 independently represents a hydrocarbon group which may contain an aromatic group having 1-12 carbon atoms; each of R.sup.3-R.sup.6 and R.sup.9-R.sup.16 represents a hydrogen atom or an aliphatic or aromatic substituents; each of j, k, r and s independently represent an integer of 0 or more; and each of m, n, p and q independently represents 1 or 2) (In formula (2), each of R.sup.7, R.sup.8, R.sup.17 and R.sup.18 independently represent a hydrocarbon group which may contain an aromatic group having 1-12 carbon atoms; each of R.sup.9-R.sup.16 and R.sup.19-R.sup.26 represents a hydrogen atoms or an aliphatic or aromatic substituents; and each of r, s, t and u independently represents an integer of 0 or more.)

The present invention relates to a process for preparing a polyester carbonate on the basis of aliphatic diacids and aliphatic diols and to the polyester carbonate prepared according to the process and to a moulding mass and moulding body containing the polyester carbonate. The process according to the invention is a direct synthesis in which all structural elements forming the subsequent polyester carbonate are already present as monomers in the first process step and in which two catalysts are used.

Provided is a compound represented by General Formula (1)

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in General Formula (1), Ar.sub.1 and Ar.sub.2 independently represent a group selected from the following Formulae,

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In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; a stirring blade extending from the stirring shaft in the cylindrical tank; a reactant solution inlet located on the bottom; and a reaction solution outlet located on the bottom. The reactor can be used for the polymerization of a polycarbonate oligomer.

The present application provides a polycarbonate resin including structural units (A) represented by general formula (1) and structural units (B) represented by general formula (4).

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(In general formula (1), R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, and R.sub.8 each independently represents a hydrogen atom, etc., and X represents —O—, etc.)

##STR00002##

(In general formula (4), R.sub.z and R.sub.x each independently represents a hydrogen atom or a C1-3 alkyl group, i represents an integer 3-10 and p represents an integer 5-600.)

The present invention relates to a production method of a poly(ester)carbonate, including subjecting a diol and a carbonate ester to a transesterification reaction in the presence of a catalyst, wherein the catalyst comprises aluminum or a compound thereof, and a phosphorus compound.

The present application provides: a polycarbonate resin which has heat resistance and is able to be produced using a starting material that is derived from natural products; and a monomer compound which enables the achievement of this resin. A polycarbonate resin which includes a constituent unit represented by general formula (1); a monomer compound which enables the achievement of this resin; and a polycarbonate resin which includes a constituent unit represented by general formula (1) and a constituent unit represented by general formula (2).

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