摘要:
The present invention relates to a method of producing polycarbonate containing following step (a) and step (b), (a) a step of reacting a specific fluorine-containing carbonate (Compound (1), etc.) and an aromatic dihydroxy compound in the presence of a condensation catalyst, to obtain a prepolymer, and (b) a step of heating the prepolymer at a temperature which is lower than a melting temperature of the prepolymer and performing solid phase polymerization on the prepolymer while a fluorine-containing alcohol that is produced as a by-product is discharged out of a system, to obtain a polycarbonate.
摘要:
In some embodiments, a composition comprises a bisphenol-A polycarbonate, wherein a molded article of the composition has transmission level greater than or equal to 90.0% at 2.5 mm thickness as measured by ASTM D1003-00 and a yellow index (YI) less than or equal to 1.5 as measured by ASTM D1925.
摘要:
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solvent continuously or intermittently from a reactor; (B) a step of separating the polymerization reaction solution withdrawn in the step (A) into an aqueous phase and a water-insoluble organic solvent phase; and (C) a step of after washing the water-insoluble organic solvent phase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).
摘要:
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).
摘要:
The present invention relates to copolycarbonates having improved surface hardness, processes for the preparation thereof and the use thereof for the production of blends, shaped articles and extrudates.
摘要:
A process for the production of bisphenol A is disclosed. The process entails a) mixing phenol and acetone to form a mixture, and b) bringing the mixture to a temperature of 48 to 54° C. to form a warm mixture, and c) commencing a reaction between phenol and acetone upon contacting the warm mixture with an acid ion exchange catalyst to form a product mixture that contains bisphenol A. The bisphenol A may be extracted from the product mixture by crystallization and filtration.
摘要:
Branched polycarbonates are disclosed, characterized by having a branched nucleus structure derived from at least one compound of (1) .alpha., .alpha.', .alpha."tris(4-hydroxyphenyl)-1,3-5-triisopropylbenzene, (2) 1-[.alpha.-methyl-.alpha.-(4'-hydroxyphenyl)ethyl]-4-[.alpha.', .alpha.'-bis(4"-hydroxyphenyl)ethyl]benzene, (3) phloroglucinol and (4) trimellitic acid, a viscosity average molecular weight of 15,000 to 40,000, and an acetone-soluble matter of not more than 3.5% by weight. A process for efficiently producing these branched polycarbonates is disclosed.These branched polycarbonates are excellent in impact resistance and are suitable particularly for blow molding.
摘要:
Polycyclic polycarbonate (or thiol analog) oligomers are prepared from a mixture of at least one bishaloformate with at least one tetraphenol, or thio analogs thereof. Such mixture may also contain at least one dihydroxy or dimercapto compound. The oligomers are formed by the reaction of such mixtures with alkali metal hydroxides and various amines. The polycyclic oligomer mixtures may be converted to crosslinked polycarbonates or their thiol analogs.
摘要:
Polycyclic polycarbonate oligomers are prepared by the reaction of a bishaloformate and a tetrahydroxyaromatic compound (and optionally also a dihydroxy compound) in the presence of an olefinic tertiary amine and an aqueous slurry of an aldaline earth metal base. The proportion of water in the reaction mixture is up to about 15% by volume of the organic phase. The bishaloformate and hydroxy compounds, and most often also the amine, are preferably added gradually to the other materials.
摘要:
A process for producing a halogen-containing polycarbonate resin characterized by washing, with an aqueous washing liquid, an organic solvent solution of a mixture of a halogen-containing polycarbonate resin having a halogen content of not less than 4 wt % (hereinafter referred to simply as polycarbonate H) and a polycarbonate resin having a halogen content of not larger than 4 wt % (hereinafter referred to simply as polycarbonate P) the weight ratio of polycarbonate P to polycarbonate H being 0.05-4, and collecting a mixed polycarbonate resin having a halogen content of not less than 4 wt % from said solution.