362 results about "Dihydroxylation" patented technology

The disclosure provides high quality, low yellowness index copolycarbonates comprising structural units derived from at least one aliphatic diol, at least an aromatic dihydroxy compound and a diaryl carbonate. Also disclosed herein is a method of making such copolycarbonates in presence of one or more catalysts.

The relative intensity of fluorescent light of a melt-polycondensed aromatic polycarbonate produced by the transesterification process (melt polymerization process) of an aromatic dihydroxy compound and a carbonic acid diester in the presence of a catalyst comprising a basic nitrogen compound and/or a basic phosphorus compound in combination with an alkali metal compound is suppressed to 4.0x10-3 or below at a wavelength of 465 nm based on a standard substance in a fluorescent light spectrum obtained by the excitation wavelength of 320 nm. An aromatic polycarbonate having good color stability, especially good stability to the deterioration of the chip color during storage of the chip in air at room temperature can be produced by the present invention.

The object is to provide a polycarbonate copolymer having excellent mechanical strength, good heat resistance, a low refractive index, a large Abbe number, a low berefringence and excellent transparency and containing a plant-derived raw material. Disclosed is a polycarbonate copolymer which comprises a constituent unit derived from a dihydroxy compound represented by the general formula (1) and a constituent unit derived from an alicyclic dihydroxy compound and has an Abbe number of 50 or greater and “a 5% heating weight loss temperature” (a temperature at which the 5% weight loss under heating is observed) of 340° C. or higher. Also disclosed is a process for producing the polycarbonate copolymer by reacting a dihydroxy compound represented by the general formula (1) and an alicyclic dihydroxy compound with a carbonate diester in the presence of a polymerization catalyst.

The above-described and other deficiencies of the art are met by a method of making a polycarbonate polymer comprising isosorbide carbonate units, comprising melt reacting a dihydroxy compound comprising an isosorbide of the general formula (2a):

and an activated carbonate, in the presence of a catalyst consisting essentially of a sodium salt capable of providing a hydroxide ion, wherein the polycarbonate polymer comprises greater than or equal to 50 mol % isosorbide carbonate units, and wherein the polycarbonate polymer has a Mw of greater than or equal to about 40,000 g/mol as determined by gel-permeation chromatography relative to polystyrene standards. Polycarbonates comprising the isosorbide carbonate unit, including isosorbide homopolycarbonate and an isosorbide-based polyester-polycarbonate, are also disclosed, as are a thermoplastic composition and an article including the isosorbide-based polycarbonate polymer.

Polycarbonates incorporating terminal carbonate groups derived from ester-substituted activated carbonates, for example terminal methyl salicyl carbonate (TMSC) derived from the use of BMSC as the activated carbonate in a transesterification process, have unfavorable properties with respect to color, hydrolytic stability and thermal stability, particularly when the polycarbonate containing such end groups is molded. The number of activated carbonate end groups formed during the melt transesterification formation of polycarbonate can be reduced, however, without sacrificing the benefits of using an activated diaryl carbonate, and without requiring a separate reaction or additional additives by reacting a dihydroxy compound with an activated diaryl carbonate in the presence of an esterification catalyst to produce a polycarbonate, wherein the molar ratio of activated diaryl carbonate to dihydroxy compound is less than 1 when expressed to at least three decimal places, for example 0.996 or less.

Polycarbonates incorporating terminal carbonate groups derived from ester-substituted activated carbonates in a transesterification process have unfavorable properties with respect to color, hydrolytic stability and thermal stability, particularly when the polycarbonate containing such end groups is molded. The number of activated carbonate end groups formed during the melt transesterification formation of polycarbonate can be reduced by reacting a dihydroxy compound with an activated diaryl carbonate in the presence of an esterification catalyst to produce a polycarbonate, in the presence of a monohydroxy chainstopper such as para-cumyl phenol in an amount that results in 35 to 65 mol % of the end groups being derived from the monohydroxy chainstopper. Suitably, the reactants are provided such that the molar ratio of activated diaryl carbonate to the total of dihydroxy compound plus ½ the chainstopping reagent that is less than 1.

A subject for the invention relates to processes for producing a polycarbonate containing a plant-derived starting material and to molded articles thereof, the polycarbonate having excellent mechanical strength, heat resistance, a low refractive index, a large Abbe number, low birefringence, and excellent transparency. The invention relates to a process for producing a polycarbonate which includes a step in which one or more dihydroxy compounds including a dihydroxy compound having at least one linking group —CH₂—O— in the molecule thereof are reacted with a carbonic acid diester in the presence of a polymerization catalyst, wherein the dihydroxy compound having at least one linking group —CH₂—O— in the molecule thereof has a formic acid content lower than 20 ppm. The invention further relates to a molded article constituted of a polycarbonate or a composition of the polycarbonate, the polycarbonate being a polycarbonate which contains constituent units derived from a dihydroxy compound having at least one linking group —CH₂—O— in the molecule thereof and has an Abbe number of 50 or larger and a 5% weight loss temperature of 340° C. or higher.

A process for manufacturing an α-dihydroxy derivative from an aryl allyl ether wherein such α-dihydroxy derivative can be used to prepare an α-halohydrin intermediate and an epoxy resin prepared therefrom including epoxidizing an α-halohydrin intermediate produced from a halide substitution of an α-dihydroxy derivative which has been obtained by a dihydroxylation reaction of an aryl allyl ether in the presence of an oxidant or in the presence of an oxidant and a catalyst.

The invention discloses a preparation method for a triazine hyperbranched macromolecular carbon forming agent. The method is characterized by comprising the following steps: 1), mixing diamino or hydroxyl compound with non-protonic organic solvent, and adding catalyst in the atmosphere of inert gases; 2), dropwise adding cyanuric chloride non-protonic organic solution, and continuing the reaction at the temperature after finishing dropwise adding the cyanuric chloride non-protonic organic solution; 3), adding blocking agent, and carrying out reaction again; and 4), precipitating, filtering, cleaning the organic solvent, separating, and drying to obtain the triazine hyperbranched macromolecular carbon forming agent. Compared with the prior art, the invention has the advantages that the 'one-pot' method is adopted, the reaction process is continuous, the reaction time is short, the product has favorable heat stability, the carbon forming rate is high, and the processability is good.

A polycarbonate resin reduced in the release of environmental hormones which comprises structural units represented by general formula (A) and structural units represented by general formula (B), the structural units represented by general formula (A) accounting for 5 to 90 mol % of all the structural units, and which has an intrinsic viscosity of 0.30 to 0.60 dl/g. The polycarbonate resin is produced through the copolymerization of a bispenol whose ability to link to estrogen acceptors is low with an aliphatic dihydroxy compound. The resin hence has the basic properties inherent in polycarbonates, i.e. mechanical strength and heat resistance, and is reduced in the release of environmental hormones.

A composition of matter comprising a thermoplastic resin composition derived from (i) about 20 weight percent to about 80 weight percent of a polyester derived from a diol comprising cyclohexane dimethanol and a diacid; (ii) about 5 weight percent to about 80 weight percent of a copolycarbonate derived from about 20 weight percent to about 70 weight percent of a 2-hydrocarbyl-3,3-bis(hydroxyaryl)phthalimidine and from about 30 weight percent to about 80 weight percent of a second aromatic dihydroxy compound; (iii) about 0 weight percent to about 70 weight percent of a thermoplastic resin, C wherein the thermoplastic resin C is selected from the group consisting of a homopolycarbonate, a poly(estercarbonate), a poly(arylatecarbonate) and combinations thereof, and wherein the resin composition is transparent is disclosed. Also disclosed is a process to prepare this composition and articles therefrom.

The present invention relates to: a polycarbonate diol which contains a structural unit derived from a compound represented by formula (A) and a structural unit derived from a compound represented by formula (B), and which has a hydroxyl number of 20-450 mg-KOH/g; and a polycarbonate diol which has a hydroxyl number of 20-45 mg-KOH/g and a glass transition temperature of -30°C or less as measured by a differential scanning calorimeter, and which provides, by hydrolysis, a dihydroxy compound that has an average number of carbon atoms of 3-5.5.

A subject for the invention is to provide a branched aromatic polycarbonate which is excellent in hue and in melt characteristics such as melt strength.

The invention provides a branched aromatic polycarbonate having a viscosity-average molecular weight of 16,000 or higher obtained by the transesterification method, characterized in that the ratio of the weight-average molecular weight (Mw) to number-average molecular weight (Mn) as measured by gel permeation chromatography and calculated for standard polystyrene (Mw/Mn) is in the range of from 2.8 to 4.5 and that the proportion of the number of moles of all structural units yielded by a rearrangement reaction in the course of melt polymerization reaction to 1 mol of structural units having the framework of an aromatic dihydroxy compound used as a starting material is higher than 0.3 mol % and not higher than 0.95 mol.

LDH-osmate of the formula [MII(1-x)MIIIx(OH)2][OsO42-]x/2.zH2O wherein MII is a divalent cation selected from the group consisting of Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+ and Ca2+ and MIII is a trivalent ion selected from the group consisting of Al3+, Cr3+, Mn3+, Fe3+ and Co3+, and x is the mole fraction having integral value ranging from 0.2 to 0.33, and z is the number of water molecules and ranges from 1 to 4, useful as, a catalyst, and a process for the preparation thereof and use thereof to manufacture vicinal diols.

The polycarbonate resin of the invention includes a first structural unit derived from a dihydroxy compound represented by a general formula (1), a second structural unit derived from a dihydroxy compound represented by a general formula (2), and a third structural unit derived from at least one dihydroxy compound selected from the group consisting of a dihydroxy compound represented by a general formula (3), a dihydroxy compound represented by a general formula (4), a dihydroxy compound represented by a general formula (5), and a dihydroxy compound represented by a general formula (6), and in which the first structural unit derived from a dihydroxy compound represented by the general formula (1) accounts for 18% by mole or more of the polycarbonate resin. The above general formulae (1) to (6) are described in the specification of the present application.

The invention relates to a method for preparing polycarbonate through basic ionic liquid catalysis. The method is characterized in that quaternary ammonium and quaternary phosphonium basic ionic liquid serves as a catalyst, the dosage of the catalyst is 5*10<-3>%-5% that of a dihydroxy compound, the dihydroxy compound and dialkyl carbonate serve as the raw materials, the feeding molar ratio of the dihydroxy compound to dialkyl carbonate is 1:0.8 to 1:10, and polycarbonate is synthesized through melting ester exchange. The synthetic processes of polycarbonate comprise the two stages of ester exchange and polycondensation, wherein for the ester exchange stage, on the condition that the reaction temperature ranges from 98 DEG C to 150 DEG C, the pressure is atmospheric pressure, and the reaction time ranges from 3 h to 6 h, prepolymer is obtained, and for the polycondensation stage, polycarbonate is obtained by synthesizing the prepolymer on the condition that the temperature ranges from 210 DEG C to 260 DEG C, the vacuum degree ranges from 4.0*10<-3> MPa to 1.0*10<-5> MPa, and the reaction time ranges from 1 h to 7 h. The synthetic method has the following advantages that the catalyst is simple in component and high in activity, a by-product phenol can be recycled, and the cost is reduced; toxic phosgene is cleared off, and the method is environmentally friendly; zero emission is almost achieved, and the method completely conforms to the concept of cleaning production.

A method of preparing polycarbonate includes a steps of providing a melt reaction mixture and allowing the melt reaction mixture to react to build molecular weight, thereby preparing the polycarbonate. The melt reaction mixture has a dihydroxy compound, an ester substituted diaryl carbonate mixture, and a melt transesterification catalyst where the ester substituted diaryl carbonate mixture may contain acid-substituted phenol. The method also includes the step of adjusting the molar ratio of acid-substituted phenol, if present, to melt transesterification catalyst (acid-substituted phenol/catalyst) in the melt reaction mixture to an amount of less than 10.

The present inventions provide a novel polycarbonate copolymer having high fluidity and high molecular weight which is formed of a structural unit derived from an aliphatic diol compound and a structural unit derived from an aromatic dihydroxy compound, having a structure represented by the formula (III):

having the content of the structural unit derived from the aliphatic diol compound of 1-30 mol %, having the Q-value (280° C., 160 kg load) in the range from 0.02 to 1.0 ml/s, and having the weight average molecular weight (Mw) of 30,000 to 100,000, and an aromatic polycarbonate compound which is formed of a structural unit derived from an aromatic dihydroxy compound which is suitable for a prepolymer for producing a high fluidity polycarbonate copolymer