Abstract: A non-reactive monomer mixture has a monomer component dispersed in a melted diaryl carbonate. The monomer component has one or more monomer compounds having a melting point below the melting point of the diaryl carbonate. Furthermore, the monomer component has less than 600 ppb alkali metal, an acid stabilizer, or both less than 600 ppb alkali metal and an acid stabilizer. The monomer compounds of the monomer component and the diaryl carbonate are present in a mole ratio of from 0.9 to 1.1. The monomer mixture is at a temperature between the melting temperature of the lowest melting monomer compound and the melting temperature of the diaryl carbonate.

Abstract: A non-reactive monomer mixture is formed from a dihydroxy component having one or more dihydroxy compounds dissolved in a melted diaryl carbonate. The dihydroxy component has less than 600 ppb alkali metal, an acid stabilizer, or both less than 600 ppb alkali metal and an acid stabilizer. The dihydroxy compounds of the dihydroxy component and the diaryl carbonate are present in a mole ratio of from 0.9 to 1.1. The monomer mixture is at a temperature between the saturation point of the monomer mixture and the highest melting temperature of the individual dihydroxy compounds. The non-reactive monomer mixture can be stored and transported and then polymerized to form polycarbonate upon addition of a catalyst.

Abstract: 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.

Abstract: A surface of a melt polymerization reactor system having residual reaction components of a melt polymerization reaction thereon can be cleaned by introducing a cleaning agent having a phenolic compound to the polymerization reactor system and into contact with the surface of the melt polymerization reactor system having the residual reaction components of a melt polymerization reaction thereon. The residual reaction components of the melt polymerization reaction include polycarbonate oligomers or polymers or their degradation products. Further, the cleaning agent is maintained in contact with the surface for a period of time and at a temperature sufficient to substantially remove the residual reaction components from the surface.

Abstract: A method for preparing a molded article includes the steps of (a) obtaining a polycarbonate resin and (b) molding the polycarbonate resin. The polycarbonate resin is made by a transesterification reaction using an activated diaryl carbonate such that the polycarbonate is susceptible to the formation of internal ester linkages (IEL). The method occurs with the proviso that the polycarbonate resin, the molding conditions or both are selected to control the amount of IEL formed during the molding process to a level of less than 0.4 mol %.

Abstract: A method of making polycarbonate includes the steps of forming polycarbonate by a melt transesterification method using an activated diaryl carbonate, and compounding the polycarbonate with a phosphorus-containing compound that has an abstractable proton or hydrolyzable group. The phosphorus-containing compound is compounded with the polycarbonate in an amount sufficient to result in an improvement in the color properties of the polycarbonate as compared to pellets formed from the same polycarbonate without addition of the phosphorus-containing compound.

Abstract: A method of increasing the branching and polydispersity of a polycarbonate includes the steps of: (a) including in the polycarbonate at least one species of an alkyl substituted monomer, and (b) treating the polycarbonate at an elevated temperature and for a sufficient time to increase the branching and polydispersity relative to an otherwise equivalent polycarbonate without alkyl substituents.

Abstract: A process for the production of polycarbonate having increased end-cap levels, the process comprising adding a terminal blocking agent of the formula: wherein R1 is a propoxy or butoxy and R2 is selected from the group consisting of C1-C30 alkyl, C1-C30 alkoxy, C6-C30 aryl, C7-C30 aralkyl, and C6-C30 aryloxy.

Abstract: In various embodiments the present invention comprises 2,4,6-trisubstituted-1,3,5-triazine capping agents comprising one, two, or three leaving groups as substituents with any remaining substituents being essentially inert to reaction with a nucleophilic group on a polymer or monomer, or reactive with a nucleophilic group on a polymer or monomer at a slower rate than any leaving group. The invention also comprises polymers or monomers with nucleophilic groups capped with a triazine moiety. Still other embodiments of the invention comprise processes for capping nucleophilic groups in a polymer or monomer which comprises combining and reacting the polymer or monomer with a triazine-comprising capping agent.

Abstract: A surface of a melt polymerization reactor system having residual reaction components of a melt polymerization reaction thereon can be cleaned by introducing a cleaning agent having a phenolic compound to the polymerization reactor system and into contact with the surface of the melt polymerization reactor system having the residual reaction components of a melt polymerization reaction thereon. The residual reaction components of the melt polymerization reaction include polycarbonate oligomers or polymers or their degradation products. Further, the cleaning agent is maintained in contact with the surface for a period of time and at a temperature sufficient to substantially remove the residual reaction components from the surface.

Abstract: A method for preparing a membrane to be assembled in a membrane, electrode assembly includes the step of swelling an ion-conducting membrane in a liquid containing at least one solvent or to an atmosphere containing the vapor phase of at least one solvent by controlling the content of the solvent in the ion-conducting membrane. A method for manufacturing a membrane electrode assembly using an ion conducting membrane includes the steps of: providing an ion-conducting membrane in a pre-swollen state; coating the ion-conducting membrane on both sides with an electrode layer to form a sandwich; and hot-pressing the sandwich to form an ion-conducting bonding of the layers of the sandwich. Furthermore, a membrane electrode assembly is disclosed including a hot pressed sandwich having an electrode layer, a ion-conducting membrane and again an electrode layer, thereby using the ion-conducting membrane in its pre-swollen status prior to the hot-pressing.

Abstract: According to the present invention a method for grafting a chemical compound to a predetermined region of a support substrate (4) is disclosed, comprising: a) irradiating selectively the support substrate with electromagnetic radiation and/or particle radiation in order to both define said predetermined region and to form at least one reactive functional group or a precursor thereof in said predetermined region of the support substrate; b) exposing the irradiated support substrate to said chemical compound or to a precursor thereof. Therefore, only these very few steps are needed to effectively grafting the desired chemical compound, such as an organic compound, to the predetermined regions of the support substrate. Moreover, the irradiation step can be carried out in a vastly flexible manner and allows to generate numerous distinct shapes of the predetermined regions.

Abstract: Alkyl ester end-capped polycarbonates have improved release properties and may be produced by a method comprising the step of combining a polycarbonate having free terminal OH groups with an end-capping reagent comprising a symmetrical activated carbonate and an alkyl ester, whereby the end-capping reagent reacts with at least some of the free hydroxyl end groups of the polycarbonate to produce an end-capped polycarbonate comprising optionally substituted aliphatic ester end groups.

Abstract: Alkyl ester end-capped polycarbonates have improved release properties and may be produced by a method comprising the step of combining a polycarbonate having free terminal OH groups with an end-capping reagent comprising a symmetrical activated carbonate and an alkyl ester, whereby the end-capping reagent reacts with at least some of the free hydroxyl end groups of the polycarbonate to produce an end-capped polycarbonate comprising optionally substituted aliphatic ester end groups.

Abstract: A process for the production of polycarbonate having increased end-cap levels, the process comprising adding a terminal blocking agent of the formula: 1

Abstract: A method for preparing a polycarbonate comprises preparing a free hydroxyl-containing polycarbonate and reacting the hydroxyl-containing polycarbonate with a mixture of (B) a symmetrical optionally activated aromatic carbonic acid diester and (C) an optionally substituted aromatic hihydroxy compound, diol or diacid. A copolymerization reagent comprises a mixture of (B) a symmetrical optionally activated aromatic carbonic acid diester and (C) an optionally substituted aromatic hihydroxy compound, diol or diacid. A copolymer comprises [polycarbonate]x moieties; (B) [symmetrical optionally activated aromatic carbonic acid diester]y moieties and (C) [optionally substituted aromatic hihydroxy compound, diol or diacid]z moieties, wherein x, y and z are mole percents of the copolymer.

Abstract: Polycarbonate compositions incorporating long chain alkylphenol endgroups, for example cardanol, show enhanced pit replication characteristics when molded into optical disks. The enhancement in molding performance is especially pronounced at the shortest mold cycle times tested. Thus, a blend of 75 parts by weight bisphenol A polycarbonate 92 percent encapped with phenol, and 25 parts by weight bisphenol A polycarbonate about 100 percent endcapped with cardanol showed enhanced pit replication performance in optical disk molding trials relative to the same bisphenol A polycarbonate alone and analogous blends utilizing short chain alkylphenols.

Abstract: A method for end-capping polycarbonate resins, comprising the step of processing a mixture comprising a polycarbonate having free hydroxyl-end groups and an end-capping reagent in a melt transesterification reaction to produce a polycarbonate resin, wherein the end-capping reagent comprises a mixture of: (a) at least one species of a symmetrical activated aromatic carbonate, and (b) at least one species of an optionally-substituted phenol, whereby said end-capping reagent reacts with at least some of the free hydroxyl end-groups of the polycarbonate to produce an end-capped polycarbonate resin.

Abstract: A method for end-capping polycarbonate resins, comprising the step of processing a mixture comprising a polycarbonate having free hydroxyl-end groups and an end-capping reagent in a melt transesterification reaction to produce a polycarbonate resin, wherein the end-capping reagent comprises a mixture of: (a) at least one species of a symmetrical activated aromatic carbonate, and (b) at least one species of an optionally-substituted phenol, whereby said end-capping reagent reacts with at least some of the free hydroxyl end-groups of the polycarbonate to produce an end-capped polycarbonate resin.

Abstract: A process for the production of polycarbonate by melt-polycondensing an aromatic dihydroxy compound and diphenylcarbonate, the process comprising adding the to polycarbonate under melt conditions a compound of the formula (1): wherein R1 and R3 may be the same or different and are selected from the group consisting of alkoxy, phenoxy, benzoxy, aryloxy, phenyl and aryl groups, R2 is selected from the group consisting of alkyl, phenyl, aryl, or aralkyl groups.