Provided are a method for manufacturing polycarbonate polyol and a composition including the polycarbonate polyol. The composition includes polycarbonate polyol; a plurality of nanoscale silicate platelets having 10,000 to 20,000 (units/per platelet) of metal cations on surfaces thereof, wherein the polycarbonate polyol has a viscosity of from 265 to 1520 cps.

Provided are a method for manufacturing polycarbonate polyol and a composition including the polycarbonate polyol. The composition includes polycarbonate polyol; a plurality of nanoscale silicate platelets having 10,000 to 20,000 (units/per platelet) of metal cations on surfaces thereof, wherein the polycarbonate polyol has a viscosity of from 265 to 1520 cps.

The purpose of the present invention is to provide an aromatic polycarbonate oligomer solid which has a markedly reduced amount of a low molecular weight component, has no or a markedly reduced amount of chlorine-containing compounds, has a high loose bulk density and is easy to handle. The purpose is met by an aromatic polycarbonate oligomer solid which includes a repeating unit represented by general formula (1), has a weight average molecular weight of 500 to 10000, has a low molecular weight component of less than or equal to 5.0 area % as measured by high performance liquid chromatography, and has a loose bulk density of greater than or equal to 0.20 g/cm.sup.3. ##STR00001##

A polycarbonate resin composition, a molded article, a polycarbonate resin, and an end-capping agent for polycarbonate resins are provided. The polycarbonate resin composition contains: a polycarbonate resin having a terminal structure represented by Formula (A) and having a viscosity average molecular weight from 110.sup.4 to 510.sup.4, and a stabilizer. In Formula (A), R.sup.1 is selected from the group consisting of a hydrogen atom, halogen atoms, linear alkyl groups having from 1 to 9 carbons, branched alkyl groups having from 3 to 9 carbons, linear alkenyl groups having from 2 to 9 carbons, branched alkenyl groups having from 3 to 9 carbons, and aryl groups having from 6 to 12 carbons; and R.sup.2 to R.sup.7 are each independently selected from the group consisting of a hydrogen atom, alkyl groups having from 1 to 9 carbons, and alkoxy groups having from 1 to 9 carbons.

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A polycarbonate resin composition, a molded article, a polycarbonate resin, and an end-capping agent for polycarbonate resins are provided. The polycarbonate resin composition contains: a polycarbonate resin having a terminal structure represented by Formula (A) and having a viscosity average molecular weight from 110.sup.4 to 510.sup.4, and a stabilizer. In Formula (A), R.sup.1 is selected from the group consisting of a hydrogen atom, halogen atoms, linear alkyl groups having from 1 to 9 carbons, branched alkyl groups having from 3 to 9 carbons, linear alkenyl groups having from 2 to 9 carbons, branched alkenyl groups having from 3 to 9 carbons, and aryl groups having from 6 to 12 carbons; and R.sup.2 to R.sup.7 are each independently selected from the group consisting of a hydrogen atom, alkyl groups having from 1 to 9 carbons, and alkoxy groups having from 1 to 9 carbons.

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A method of preparing a partially crystalline polycarbonate powder, including: dissolving an amorphous polycarbonate in a halogenated alkane solvent to form a solution; combining the solution with a crystallizing non-solvent that is miscible with the halogenated alkane solvent, under high shear mixing conditions effective to form a partially crystalline polycarbonate precipitate having a D90 particle size of less than 150 micrometers; an average particle diameter of less than or equal to 100 micrometers, or an average particle diameter of 0 to 100 micrometers; and at least 20% crystallinity, or at least 25% crystallinity, or 25 to 35% crystallinity.

A method of preparing a partially crystalline polycarbonate powder, including: dissolving an amorphous polycarbonate in a halogenated alkane solvent to form a solution; combining the solution with a crystallizing non-solvent that is miscible with the halogenated alkane solvent, under high shear mixing conditions effective to form a partially crystalline polycarbonate precipitate having a D90 particle size of less than 150 micrometers; an average particle diameter of less than or equal to 100 micrometers, or an average particle diameter of 0 to 100 micrometers; and at least 20% crystallinity, or at least 25% crystallinity, or 25 to 35% crystallinity.

The present invention relates to a production method of polyalkylene carbonate particles capable of precipitating and separating resin particles from a polyalkylene carbonate suspension obtained through polymerization of an epoxide and carbon dioxide. According to the present invention, the production method is capable of obtaining a polyalkylene carbonate resin having excellent workability with a high yield and a low energy cost while reducing a scale of a facility, a processing time, and a wastewater amount, as compared to conventional methods such as a flash separation method.

The present invention provides a method for preparing a polycarbonate by removing a solvent from a polycarbonate polymerization solution without impairing the physical properties of the polycarbonate.

The present invention relates to a method for purifying polyalkylene carbonate. More specifically, a method for purifying polyalkylene carbonate is provided, which uses a multistage extraction column having the number of stages of at least 10 stages, using water for effectively removing by-products such as alkylene carbonate generated in a process for producing polyalkylene carbonate resin, thereby controlling the content of by-products to a certain level or less through a continuous operation, particularly, the extraction is performed at room temperature, thereby easily removing by-products in the resin without a high temperature volatilization.