Abstract: An improvement to the transesterification process for the production of aromatic polycarbonates is disclosed. Into the melt which contains diphenols, carbonic acid diaryl esters and optionally branching agents and at temperatures of 130.degree. C. to 400.degree. C. and in the presence of catalysts there is mixed or passing thereover inert gas in a quantity of at least 0.5 Nm3 per kg of polycarbonate melt.

Abstract: A process for the preparation of a substantially chlorine-free, high-molecular-weight, colorless and transparent (co)polycarbonate by melt-polycondensing a dihydroxy compound with a carbonic diester, which comprises using a carbonic diester which satisfies at lease one factor selected from the group consisting of:(factor-1) the carbonic diester is substantially free from phenyl salicylate, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate,(factor-2) the carbonic diester is substantially free from tin ion, and(factor-3) the carbonic diester is substantially free from methyl phenyl carbonate.

Abstract: A polycarbonate derived from a novel dihydroxy compound having a triphenylamine structure, and a process for producing the polycarbonate are disclosed. The polycarbonate is obtained by reacting a dihydroxy compound having a triphenylamine structure described hereinbefore and a carbonate precursor, or by reacting the dihydroxy compound, a dihydric phenol compound and the carbonate precursor. The polycarbonate is useful as a plastic molding material or as a material for forming a polymer alloy with other resin.

Abstract: The present invention provides a transesterification process for the production of thermoplastic, solvent-free polycarbonates by the use of catalysts that are derived from guanidine.

Abstract: The method of this invention prepares copolymeric polycarbonates which have excellent mechanical properties, heat resistance and transparency, and which also have improved chemical resistance, hue, and residence stability by inducing the melt polycondensation of an aromatic dihydroxy compound containing an amount of 2-90 mol % of hydroquinone and/or substituted hydroquinones with a diester carbonate in the presence of a catalyst containing alkali metal compounds and/or alkaline earth metal compounds in an amount of 1.times.10.sup.-8 to 5.times.10.sup.-6 mole per mole of the total amount of the aromatic dihydroxy compound.

Abstract: A method for producing polycarbonates by the interfacial reaction of phosgene bisphenol in a two phase reaction medium of an aqueous hydroxide and an organic solvent is disclosed. In the reaction, the amount of water in the reaction medium is controlled such that high ionic strength conditions resulting from high salt concentrations are reached at the end of phosgenation and the pH of the medium is controlled to a range between 8 and 10 whereby excess phosgene usage is less than about 15% of theoretical conditions.

Abstract: The invention relates to a process for the production of polycarbonates by the two-phase interfacial method in which deviations between measured and estimated variables are continuously minimized by means of a suitably selected observer or filter system on the basis of a process model with an empirical Mark-Houwink relation adapted to the process. The variables estimated by the observer/filter are converted into control variables which are used to set input streams of the production process. Product quality is kept constant, changes in load or set values are quickly intercepted and even disturbances not readily accessible to measurement are taken into account by the process control.

Abstract: A process for producing an aliphatic-aromatic polycarbonate is disclosed. The process comprise (A) reacting in an anhydrous neutral solvent (i) an oligocarbonate of diphenol with (ii) an aliphatic dicarboxylic acid, and (B) eliminating the hydrogen chloride and carbon dioxide by-products. The oligocarbonate of diphenol is characterized in that it is terminated by chlorocarbonic acid ester groups. The resins thus prepared are readily molded conventionally.

Abstract: The present invention provides copolymerized polycarbonates having improved flow and formability, in addition to excellent mechanical properties, heat resistance, transparency, and water resistance obtained by copolymerization of two or more aromatic dihydroxy compounds and a compound capable of reacting with those aromatic dihydroxy compounds to form carbonate linkages, characterized in that, of all the constituent repeating units derived from aromatic dihydroxy compounds, 2-40 mole % are derived from resorcin and/or substituted resorcins.

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).

Abstract: A copolymeric polycarbonate containing repeating constituent units having formula [I] below and repeating constituent units having formula [II] below in a molar ratio of from 98:2 to 40:60. ##STR1## The above-described copolymeric polycarbonates have excellent resistance to chemicals, heat resistance and flame retardancy without compromising the impact resistance and good hues intrinsic to polycarbonates.

Abstract: The invention relates to a two-stage process for the production of thermoplastic, solvent-free lightly branched polycarbonates in the melt using ammonium and/or phosphonium catalysts in the first stage and alkali metal and/or alkaline earth metal catalysts in the second stage.

Abstract: A process for producing a (co)polycarbonate or a (co)polyestercarbonate having a high molecular weight and excellent hue, heat stability and mechanical properties by reacting a dihydroxyl compound with a diester of carbonic acid and/or a diester of dicarbonic acid in the presence of a transesterification catalyst, wherein at least part of the reaction process is conducted in the presence of a specified organic phosphorus compound, or, in the presence of a specified organic phosphorus compound and a hindered phenol compound. A (co)polycarbonate or (co)polyester-carbonate composition having excellent hue, heat stability and mechanical properties, comprising a (co)polycarbonate and/or a (co)polyestercarbonate and, a specified organic phosphorus compound, or, a specified organic phosphorus compound and a hindered phenol compound.

Abstract: A method is provided for making polycarbonate utilizing an effective amount of a phase transfer catalyst, such as tetrabutylammonium bromide as a condensation catalyst during the interfacial phosgenation of a bisphenol, such as bisphenol A. Improved phosgene utilization is achieved.

Abstract: A poromeric material for maintaining an electrostatic charge is provided, the material including a matrix of fibers, a polymeric binder for binding the matrix, and electrets present substantially uniformly throughout the poromeric material. Also provided are methods for making the poromeric material. In one embodiment, a polymeric binder mixture having electrets substantially uniformly contained therein is formed. The matrix of fibers is impregnated with the mixture and cured, whereby the electrets are substantially uniformly distributed throughout the matrix to produce the electrostatic poromeric material. In an alternative embodiment, the electrets are contained in the fibers of the matrix. The poromeric material may be used to encase a core to form a roller, for example, a hickey-removing roller.

Abstract: [Purpose] The object of the present invention is to provide a method of product copolymerized polycarbonates having improved flow and formability, in addition to excellent mechanical properties, heat resistance, transparency, and color tone.[Constitution] A method of producing copolymerized polycarbonates by melt polycondensation of two or more aromatic dihydroxy compounds with a carbonate diester, characterized in that(i) resorcin and/or substituted resorcins are used as 2-90 mole % of the aromatic dihydroxy compounds, where the sum of all the aromatic dihydroxy compounds is taken as 100 mole %, and(ii) an alkali metal compound and/or an alkaline-earth metal compound (a) is used as the catalyst.

Abstract: A process for producing an aromatic polycarbonate by reacting an aromatic dihydroxy compound, an alkali or alkaline earth metal base and a carbonyl halide compound comprises feeding a polymerization catalyst as the carbonyl halide is fed to a mixture of the aromatic dihydroxy compound, the alkali metal or alkaline earth metal, water and an organic solvent. The molecular weight of the aromatic polycarbonate can be properly controlled, the rate of end capping is high, and coloration of the aromatic polycarbonate is less. Such aromatic polycarbonate can be produced while suppressing hydrolysis of the carbonyl halide compound and/or haloformate compound.

Abstract: The present invention discloses thermoplastic resins and methods for producing said resins utilizing a single component heterocyclic amine catalyst system. More particularly, the invention discloses resins such as high molecular weight polycarbonate resins that are produced by a solventless melt condensation reaction between diphenol carbonate (DPC) and bisphenol A (BPA) in the presence of a heterocyclic amine catalyst.

Abstract: A process for the production of polycarbonates by melt transesterification is disclosed. Accordingly, polycarbonate waste is dissolved in monophenols and at an elevated temperature and in the presence of a catalyst degraded to yield oligocarbonates, diaryl carbonates and diphenols. Following the optional separation of fillers and other additives there is produced by partial recondensation and the distillation of monophenol a higher viscosity oligocarbonate having a OH and aryl carbonate terminal groups and a weight average molecular weight of 8000 to 18000, the oligocarbonate thus produced is then polycondensed to form a polycarbonate resin.

Abstract: The present invention discloses thermoplastic resins and methods for producing said resins utilizing a single component tertiary amine catalyst system. More particularly, the invention discloses resins such as high molecular weight polycarbonate resins that are produced by a solventless melt condensation reaction between diphenyl carbonate (DPC) and bisphenol A (BPA) in the presence of tertiary amine catalyst.

Abstract: A process for preparing halogenated polycarbonate wherein the total amount of base the end pH of the aqueous phaser and the amount of coupling catalyst employed in the reaction are controlled to selected levels.

Abstract: A catalytic method for preparing thermoplastic carbonate polymers is disclosed. In the method according to the interfacial polycondensation process or the homogeneous solution process, resins which containing catalytically active groups are used as catalysts. The resulting resins are characterized by their color stability and temperature stability.

Abstract: A two step solvent-free process for the preparation of polycarbonates having a low degree of branching is disclosed. Accordingly, the process comprise(i) transesterifying in the melt, at temperatures of from 80.degree. to 250.degree. C. and under atmospheric pressure and for a time of up to five hours of diphenols and carbonic acid diaryl esters in the presence of a catalyst to form an oligocarbonate having a weight average molecular weight of from 8,000 to 18,000 and an OH-end group content of from 25 to 50%, and(ii) polycondensing of said oligocarbonate at temperatures of from 250.degree. C. to 295.degree. C. and pressures of from <500 mbar to 0. 01 mbar,said catalyst being present in an amount of 10.sup.-1 to 10.sup.-8 tool of a catalyst per tool of diphenol, said catalyst being at least one member selected from the group consisting of quaternary ammonium compounds and quaternary phosphonium compounds.

Abstract: The present invention relates to a method of preparing a copolymeric polycarbonate which comprises melt-polycondensing a mixture of an aromatic dihydroxy compound comprising hydroquinone or substituted hydroquinones and a diester carbonate in the presence of a catalyst containing alkali metal compounds and/or alkaline earth metal compounds.

Abstract: A process for preparing a halogenated polycarbonate wherein phenolic-terminated, halogenated carbonate oligomers are prepared in the presence of a coupling catalyst, and are then condensed by contact with a carbonate precursor.

Abstract: A method is provided for making aromatic polycarbonates by the melt condensation of a diaryl carbonate and an aromatic bis hydroxy compound in the presence of a condensation catalyst, such as hexahydro-2H-pyrimido[1,2-a]pyrimidine or an alkyl substituted derivative.

Abstract: The object of the present invention is to provide a process for the preparation of aromatic polycarbonates in the molten state using fluoride catalysts.

Abstract: A method is provided for making polycarbonate by phosgenating a mixture of bisphenol and phenolic chain-stopper under interfacial reaction conditions in the presence of a phase transfer catalyst. A polycarbonate is obtained which is substantially free of diarylcarbonate.

Abstract: A method is provided for making flame retardant polycarbonates by phosgenating a mixture of bisphenols having up to about 50 mole % of tetrahalobisphenols, such as tetrabromobisphenols. There is employed a mixture of a phase transfer catalyst and a tertiary organic amine to provide high molecular weight copolymer without excessive phosgene usage.

Abstract: The invention discloses an improved process for the preparation of aryl polycarbonates. The process involves reacting aryl carbonate and dihydric phenol in the melt phase with a catalyst belonging to the class of quaternary ammonium bioxyanions having the general formula: ##STR1## Wherein `X` represents a carboxylate or a phenolate group or a mixture thereof and `R` represents alkyl or aryl.

Abstract: A process for preparing polycarbonate wherein a chain terminator is added to the reaction mixture after substantial reaction of a carbonate precursor, a coupling catalyst is added to the reaction mixture after substantial reaction of the chain terminator, and base is added to the reaction mixture after reaction mixture after substantial reaction of the chain terminator in an amount sufficient to give a negative chloroformate test.

Abstract: A copolymeric polycarbonate containing repeating constituent units having formula [I] below and repeating constituent units having formula [II] below in a molar ratio of from 98:2 to 40:60. ##STR1## The above-described copolymeric polycarbonates have excellent resistance to chemicals, heat resistance and flame retardancy without compromising the impact resistance and good hues intrinsic to polycarbonates.

Abstract: A process for producing a (co)polycarbonate or a (co)polyestercarbonate having a high molecular weight and excellent hue, heat stability and mechanical properties by reacting a dihydroxyl compound with a diester of carbonic acid and/or a diester of dicarbonic acid in the presence of a transesterification catalyst, wherein at least part of the reaction process is conducted in the presence of a specified organic phosphorus compound, or, in the presence of a specified organic phosphorus compound and a hindered phenol compound. A (co)polycarbonate or (co)polyester-carbonate composition having excellent hue, heat stability and mechanical properties, comprising a (co)polycarbonate and/or a (co)polyestercarbonate and, a specified organic phosphorus compound, or, a specified organic phosphorus compound and a hindered phenol compound.

Abstract: The invention disclosed is an improved process for the preparation of high molecular weight poly(arylcarbonate), the molecular weight ranging from 45,000-60,000 (corresponding to n.sub.inh 0.8 to 1.0) The process involves heating in a controlled manner, a BPA-polycarbonate oligomer in the presence of a catalyst selected from alkali metal aryl acid, alkali metal borohydrial and a quarternary ammonium salt of bioxiyanion derived from a carboxylic acid poly(arylcarbonate)s of high molecular weight produced by the process of present invention show enhanced crystallinity.

Abstract: There is provided a polycarbonate resin composition having improved melt properties without impairing mechanical properties and transparency inherent in a polycarbonate resin, and suited for blow molding. This polycarbonate resin composition comprises (A) a polycarbonate resin having a weight-average molecular weight of 13,000 to 35,000 and (B) an ultrahigh-molecular-weight polycarbonate resin having a weight-average molecular weight of 175,000 to 300,000 and a low content of gels, and has improved flowability and structural viscosity index.

Abstract: A process for the continuous production of a thermoplastic aromatic polycarbonate is disclosed. Accordingly, in a reactor system which includes a tube reactor and a tank equipped with a stirrer, there are reacted a preheated dialkali diphenolate aqueous solution with gaseous phosgene in CH.sub.2 Cl.sub.2 and/or in chlorobenzene solution containing excess phosgene, in a mixer to form a mixed emulsion. The emulsion is then transported at least partly against the force of gravity into the tube reactor to facilitate a polycondensation reaction and in which after a residence time of at least 10 seconds and without dissipation of the heat of reaction there is added a chain terminator. The heat of reaction is dissipated in said tank and aqueous sodium hydroxide and catalyst are added to complete the reaction. The process according to the invention leads to high yields of phosgene.

Abstract: An improvement to the continuous process for the production of polycarbonates by interphase polycondensation is described. Accordingly, the organic phase and the aqueous phase are combined in a tube, forming chlorocarbonic acid ester and further alkali hydroxide is added at, or shortly after, the maximum concentration of said ester is reached. The resulting emulsion is then changed to an oil-in-water emulsion which is then separated and worked up in known manner.

Abstract: In the interfacial polymerization process for preparing aromatic carbonate polymers by reacting bisphenol-A with a carbonate precursor, the bisphenol-A is introduced to the reaction medium in a liquid form saturated with water.

Abstract: A process for preparing halogenated polycarbonate wherein the total amount of base, the end pH of the aqueous phase, and the amount of coupling catalyst employed in the reaction are controlled to selected levels.

Abstract: The invention relates to a method for the continuous preparation of carbonate oligomers by boundary face oligomerization of aromatic dihydroxy compounds with phosgene while adding base, in which the reaction is carried out in a loop-like reactor system in the absence of chain stopper and while using less than 200 ppm of catalyst related to the organic solvent using at least one static mixer and plug folw, optionally in combination with a stirred tank reactor.

Abstract: The invention relates to a method of preparing aromatic polycarbonates by catalytic interface polymerization of at least one bivalent phenol and a carbonyl halide in the presence of a polycondensation catalyst, which method is characterized in that the conversion is carried out in a two-phase system with continuous dosing of the carbonyl halide, which two-phase system is based on water and an organic solvent, in which the quantity of organic solvent at the beginning of the polycondensation lies between 10% and 75% of the quantity of organic solvent which is required at the polymerization temperature for dissolving the quantity of polycarbonate which may be formed from the quantity of bivalent phenol which is present at the beginning of the polycondensation, in that after dosing at least 20% of the carbonyl halide a remaining quantity of organic solvent is added which is at least sufficient to keep the formed polycarbonate in solution.

Abstract: A process for preparing polycarbonate wherein a chain terminator is added to the reaction mixture after substantial reaction of a carbonate precursor, a coupling catalyst is added to the reaction mixture after substantial reaction of the chain terminator, and base is added to the reaction mixture after reaction mixture after substantial reaction of the chain terminator in an amount sufficient to give a negative chloroformate test.

Abstract: A method of producing a polyether copolymer by reacting a dihalogenobenzonitrile, 1,4-bis(4'-halobenzoyl)benzene, with 4,4'-biphenol in an aprotic polar solvent in the presence of an alkali metal compound to produce a polyether copolymer having repeating units represented by the following general formula (I) ##STR1## and the repeating units represented by the following formula (II) ##STR2## The molar ratio of the repeating units represented by the formula (I) based on the total of the repeating units represented by the formula (I) and the repeating units represented by the formula (II) (the molar ratio of (I)/{(I)+(II)}) is from 0.1 to 0.8. The polyether copolymer has a melt viscosity (the viscosity under no shearing stress) of at least 500 poise as measured 400.degree. C.

Abstract: A polycarbonate is produced by melt-polycondensing a dihydric hydroxy compound and a bisarylcarbonate in the presence of 4-(4-methyl-1-piperidinyl)-pyridine, or a salt thereof, as a catalyst. The process of the invention eliminates the use of poisonous phosgene, prevents chloride ions from being incorporated into the product polycarbonate and remains in the reaction system longer to enable the preparation of high-molecular weight polycarbonates.

Abstract: Disclosed herein are processes for the production of polycarbonates by melt polycondensation of an aromatic dihydroxy compound and a carbonic acid diester or a diphenyl carbonate compound wherein said polycondensation is carried out in the presence of from 0.05 to 15 mol %, based on 1 mole of the aromatic dihydroxy compound, of a phenol having from 10 to 40 carbon atoms, a carbonic acid diester having from 17 to 50 carbon atoms, or a carbonic acid diester having from 13 to 16 carbon atoms, using a catalyst comprising (a) a nitrogen containing basic compound, (b) from 10.sup.-8 to 10.sup.-3 mole, based on 1 mole of the aromatic dihydroxy compound, of an alkali metal or alkaline earth metal compound, and (c) boric acid or boric ester. Also disclosed is a polycarbonate in which from 5 to 30% of its terminal groups are hydroxy groups and it has a sodium content of not more than 1 ppm and a chlorine content of not more than 20 ppm.

Abstract: A polycarbonate is produced by melt-polycondensing a dihydric hydroxy compound and a bisarylcarbonate in the presence of a catalyst system comprising an electron donative amine compound and a compound selected from among alkali metal compounds and alkaline earth metal compounds. The process of the invention eliminates the use of poisonous phosgene, prevents chloride ions from being incorporated into the product polycarbonate and remains in the reaction system longer to enable the preparation of high-molecular weight polycarbonates.

Abstract: A process for preparing polycarbonates according to the invention by melt polycondensation of aromatic dihydroxy compounds and carbonic acid diesters, is characterized by using an aromatic dihydroxy compound and a carbonic acid diester, wherein the combined content of hydrolyzable chlorine in those monomers falls within the particular range. Another process for preparing polycarbonates according to the invention by melt polycondensation of aromatic dihydroxy compounds and carbonic acid diesters, is characterized by using a catalyst comprising (a) a nitrogen containing basic compound and (b) aromatic dihydroxy compound of an alkali metal or alkaline earth metal compound, or (a) and (b) and (c) boric acid or boric ester.

Abstract: A process for producing a dichloroformate of a tetrahalogenated bisphenol by an interfacial process in a high yield and a high content and a process for producing an aromatic copolycarbonate oligomer by a solution process using the resulting dichloroformate monomer are disclosed. The first process comprises adding a catalyst for chloroformate formation to a tetrahalogenated bisphenol in an amount of from 1.times.10.sup.-4 to 1.times.10.sup.-1 mol per mol of the bisphenol and consecutively adding a halogenated carbonyl to effect reaction while controlling the pH of the reaction system between 10 and 12 by consecutive addition of a basic inorganic compound to the reaction system. The copolycarbonate oligomer obtained using the dichloroformate monomer has high alternating regularity.

Abstract: A process for preparing polycarbonates according to the invention by melt polycondensation of aromatic dihydroxy compounds and carbonic acid diesters, is characterized by using an aromatic dihydroxy compound and a carbonic acid diester, wherein the combined content of hydrolyzable chlorine in those monomers falls within the particular range. Another process for preparing polycarbonates according to the invention by melt polycondensation of aromatic dihydroxy compounds and carbonic acid diesters, is characterized by using a catalyst comprising (a) a nitrogen containing basic compound and (b) aromatic dihydroxy compound of an alkali metal or alkaline earth metal compound, or (a) and (b) and (c) boric acid or boric ester.

Abstract: A method for making cyclic polycarbonate oligomers is provided by converting oligomeric monochloroformate carbonates to the cyclic state. Improvements in materials usage, process control, and product characteristics are obtained.