Abstract: The present invention is directed to an epoxidized block copolymer (E) obtained by epoxidizing a block copolymer (C) comprising a polymer block (A) composed mainly of a vinyl aromatic hydrocarbon compound and a polymer block (B) composed mainly of a conjugated diene compound or a product (D) of hydrogenation of the block copolymer (C). The epoxidized block copolymer (E) meets at least one of the following requisites: (1) having a molar ratio (R) of contained hydroxyl to epoxy ranging from 0.001 to 0.

Abstract: The present invention is directed to an epoxidized block copolymer composition comprising an epoxidized block copolymer (E) obtained by epoxidizing a block copolymer (C) comprising a polymer block (A) composed mainly of a vinyl aromatic hydrocarbon compound and a polymer block (B) composed mainly of a conjugated diene compound or a product (D) of hydrogenation of the block copolymer (C). The epoxidized block copolymer (E) meets at least one of the following requisites: (1) having a molar ratio (R) of contained hydroxyl to epoxy ranging from 0.001 to 0.

Abstract: Disclosed are a polymer alloy comprising a polyester resin having a specified acid value, an epoxidized diene-based block copolymer, and an unvulcanized rubber, a composition in which an unvulcanized rubber is mixed with the polymer alloy, and parts for tires in which the composition is employed.

Abstract: Disclosed are a curable composition, a cured article therefrom having improved properties, an asphalt emulsion, an asphalt mixture for paving, and a cured article prepared therefrom having an excellent water permeability.

Abstract: A process for producing an epoxidized block copolymer, which comprises the steps of: (1) mixing a block copolymer (C) comprising a polymer block (A) composed mainly of a vinyl aromatic hydrocarbon compound and a polymer block (B) composed mainly of a conjugated diene compound, or a hydrogenation product (D) of the block copolymer (C), with an organic solvent so as to obtain an organic solvent solution or organic solvent slurry having a polymer concentration of 5 to 50% by weight; (2) epoxidizing unsaturated carbon bonds contained in a polymer block (B) composed mainly of a conjugated diene compound with an epoxidizing agent that is an acetic ester solution of peracetic acid, not containing water; and (3) evaporating off the organic solvent from the reaction mixture to thereby obtain an epoxidized block copolymer.

Abstract: A processes for producing a (co)polycarbonate having a low terminal hydroxyl group concentration and being excellent in heat resistance and hue, which comprises melt-polycondensing a dihydroxy compound with a carbonic diester in the presence of a catalyst for transesterification selected from the group consisting of a nitrogen-containing basic compound, an alkali metal borate and an alkaline earth metal borate and in the presence of a specific ester compound.

Abstract: A processes for producing a (co)polycarbonate having a low terminal hydroxyl group concentration and being excellent in heat resistance and hue, which comprises melt-polycondensing a dihydroxy compound with a carbonic diester in the presence of a catalyst for transesterification selected from the group consisting of a nitrogen-containing basic compound, an alkali metal borate and an alkaline earth metal borate and in the presence of a specific ester compound.

Abstract: A processes for producing a (co)polycarbonate having a low terminal hydroxyl group concentration and being excellent in heat resistance and hue, which comprises melt-polycondensing a dihydroxy compound with a carbonic diester in the presence of a catalyst for transesterification selected from the group consisting of a nitrogen-containing basic compound, an alkali metal borate and an alkaline earth metal borate and in the presence of a specific ester compound.

Abstract: In a process for producing a polycarbonate by subjecting a dihydroxy compound and a diester of carbonic acid to melt polycondensation through transesterification, after a polycarbonate prepolymer is prepared in the first-stage reaction, polycondensation is conducted as the second-stage reaction in a residence time in the range of from 15 to less than 60 min or through the use of at least one paddle-type self-cleaning twin-screw extruderThis process enables a colorless, transparent polycarbonate having a high molecular weight to be produced at a high efficiency on an industrial scale.

Abstract: A polycarbonate is produced by transesterification from a dihydroxy compound such as 2,2-bis(4-hydroxyphenyl)propane and a diester of carbonic acid such as bisphenyl carbonate in a reactor made of stainless steel and treated by electropolishing or acid pickling or buffed on a surface part thereof which contacts the reactants. As the transesterification catalyst, (a) a nitrogen-containing, electron-donating compound and (b) a nitrogen-containing, electron-donating compound and an alkali metal compound or an alkaline earth metal compound are preferably used.

Abstract: A process for the preparation of a (co)polycarbonate having an excellent hue, heat resistance, residence to hydrolysis and impact resistance by transesterification with the use of an aparatuses of a low price. In the first step, a dihydroxy compound is reacted with a carbonic diester in a reactor having a surface area contacting the dihydroxy compound and the carbonic diester, a made of a material containing iron in an amount of 20% by weight or less, to give a prepolymer and, in the second step, melt-polycondensing the prepolymer in a reactor other than the reactor used in the first step.

Abstract: A processes for producing a (co)polycarbonate having a low terminal hydroxyl group concentration and being excellent in heat resistance and hue, which comprises melt-polycondensing a dihydroxy compound with a carbonic diester in the presence of a catalyst for transesterification selected from the group consisting of a nitrogen-containing basic compound, an alkali metal borate and an alkaline earth metal borate and in the presence of a specific ester compound.A process for producing a linear, high-molecular weight (co)polycarbonate being excellent in heat resistance, hydrolysis resistance, hue and impact resistance which comprises melt-polycondensing a dihydroxy compound with a carbonic diester in the presence of a catalyst for transesterification selected from the group consisting of specific borates.

Abstract: A polycarbonate is produced by transesterification from a dihydroxy compound such as 2,2-bis(4-hydroxyphenyl)propane and a diester of carbonic acid such as bisphenyl carbonate in the presence of a substance which contains iron in an amount of 50% by weight or less and contacts the reactants. Alternatively, a polycarbonate is produced by transesterification from a dihydroxy compound and a diester of carbonic acid in a reactor made of stainless steel and treated by electropolishing or acid pickling or buffed on a surface part thereof which contacts the reactants. As the transesterification catalyst, (a) a nitrogen-containing, electron-donating compound and (b) a nitrogen-containing, electron-donating compound and an alkali metal compound or an alkaline earth metal compound are preferably used.

Abstract: A polycarbonate which is not discolored and is substantially free from chlorine ions causative of discoloration, has a branching parameter G of 0.1 to 1.0 and, terminal hydroxyl groups of 20 mole % or below based on all the terminal groups of the polycarbonate, and/or, a chlorine ion concentration in the polycarbonate of 10 ppm or below, and/or, a total of an alkali metal ion concentration and an alkaline earth metal ion concentration in the polycarbonate of 1 ppm or below. A process for preparing the above polycarbonate by the melt transesterification process which comprises using a nitrogenous basic compound (a), and/or, a compound (b) containing an element selected from the group consisting of Groups IIb, IVb and Vb of the periodic table; or, a nitrogenous basic compound (a), and, a compound (c) containing an element selected from the group consisting of alkali metals and alkaline earth metals, as a transesterification catalyst.

Abstract: A processes for producing a (co)polycarbonate having a low terminal hydroxyl group concentration and being excellent in heat resistance and hue, which comprises melt-polycondensing a dihydroxy compound with a carbonic diester in the presence of a catalyst for transesterification selected from the group consisting of a nitrogen-containing basic compound, an alkali metal borate and an alkaline earth metal borate and in the presence of a specific ester compound.

Abstract: A polycarbonate is produced by transesterification from a dihydroxy compound such as 2,2-bis(4-hydroxyphenyl)propane and a diester of carbonic acid such as bisphenyl carbonate in the presence of a substance containing iron in an amount of 50% by weight or less to contact the reactants. Also, a polycarbonate is produced by transesterification from a dihydroxy compound and a diester of carbonic acid in a reactor made of stainless steel and treated by electropolishing or acid pickling or buffed on a surface part thereof to contact the reactants. As the transesterification catalyst, (a) a nitrogen-containing, electron-donating compound and (b) a nitrogen-containing, electron-donating compound and an alkali metal compound or an alkaline earth metal compound are preferably used.

Abstract: In a process for producing a polycarbonate by subjecting a dihydroxy compound and a diester of carbonic acid to melt polycondensation through transesterification, after a polycarbonate prepolymer is prepared in the first-stage reaction, polycondensation is conducted as the second-stage reaction at a residence time in the range of from 15 to less than 60 min or through the use of at least one paddle-type self-cleaning twin-screw extruder.This process enables a colorless, transparent polycarbonate having a high molecular weight to be produced at a high efficiency on an industrial scale.

Abstract: In a process for producing a polycarbonate by subjecting a dihydroxy compound and a diester of carbonic acid to melt polycondensation through transesterification, after a polycarbonate prepolymer is prepared in the first-stage reaction, polycondensation is conducted as the second-stage reaction at a residence time in the range of from 15 to less than 60 min or through the use of at least one paddle-type self-cleaning twin-screw extruder.This process enables a colorless, transparent polycarbonate having a high molecular weight to be produced at a high efficiency on an industrial scale.

Abstract: A process for the preparation of a (co)polycarbonate having an excellent hue, heat resistance, residence to hydrolysis and impact resistance by transesterification with the use of an aparatuses of a low price. In the first step, a dihydroxy compound is reacted with a carbonic diester in a reactor having a surface area contacting the dihydroxy compound and the carbonic diester made of a material containing iron in an amount of 20% by weight or less, to give a prepolymer and, in the second step, melt-polycondensing the prepolymer in a reactor other than the reactor used in the first step.

Abstract: A process for producing a (co)polycarbonate having excellent thermal resistance, hue and impact resistance and a high molecular weight, which comprises conducting a melt-polycondensation of a dihydroxy compound and a carbonic diester as monomers in the presence of a transesterification catalyst in a tank reactor, while removing a monohydroxy-compound formed by the melt-polycondensation, thereby obtaining a reaction mixture comprising a prepolymer in a molten state (the first step), cooling the molten reaction mixture obtained in the first step to solidify it (the second step), and conducting a melt-polycondensation of the reaction mixture comprising the prepolymer in a horizontal polycondensation reactor, thereby obtaining a reaction mixture comprising a high-molecular-weight (co)polycarbonate (the third step).